78 year old Alcoholic With Anaemia


An 78 year old man presented with fatigue and breathlessness. Examination showed pallor. There was no icretus, clubbing, lymphadenopathy or hepatomegaly. There was mild splenomegaly. There was no history of haemoptysis, malena or haematochesia.

An haemogram was performed that showed a haemoglobin was 8g/dL with an MCV of 101fl. The leucocyte count was 4.5 x 109/L and the platelet count was 265 x 109/L. The differential leucocyte count was neutrophils 58% lymphocytes 32%, monocytes 6% and eosinophils 4%. The Reticulocyte count was normal. 


Anaemia in alcoholics is multifactorial. The causes of Anaemia include

  1. Direct toxic effect of alcohol: Most alcoholics have macrocytosis in the range of 100-110fl. Macrocytosis is seen before anaemia develops. Anaemia reverses after a few months of abstaining from alcohol.
  2. Iron deficiency from gastrointestinal blood loss from varices and alcoholic gastritis may presents with hypochromic microcytic anaemeia. The transferrin saturation and serum ferritin are low. Alcohol and alcohol associated disease affect MCV, transferrin saturation and serum ferritin making interpretation of test difficult.
    • Microcytosis may not be seen in alcoholics with iron deficiency. A study showed 48% of the patients with chronic liver disease and iron deficiency diagnosed by absence of bone marrow iron had an MCV more than 100fl (J Intern Med. 1998 Mar;243(3):233-41).
    • Alcohol effects transferrin saturation. Transferrin levels may be decrease because of infection or inflammation. In a study of transferrin saturation in cirrhotics a transferrin saturation of <12% was of value in diagnosing iron deficiency. But transferrin saturation did not add to the value of ferritin in diagnosis.
    • Ferritin is an acute phase reactant and can be increase in chronic liver disease. A study has suggested different cutoffs be used in patients with chronic liver disease. Iron deficiency should be diagnosed with a ferritin ≤50 μg/L. Values >400 μg/L were associated with a low probability of iron deficiency (Annals of Gastroenterology (2017) 30, 1-9).
    • sTrasnferrin receptors levels is a iron deficiency (sensitivity 91.6%, specificity 84.6%) in patients with chronic liver disease provided that hemolysis and recent blood loss have been excluded (Clin Lab Haematol. 1999 Apr;21(2):93-7)
  3. Folate and Cobalamine deficiency: Folate and cobalamin deficiency causes macrocytosis and should be suspected in patients with MCV greater than 110fl, those with decreased platelet and/or leucocyte counts and when peripheral smear shows hypersegmantation of neutrophils.
  4. Hypersplenism: Hypersplenism causes anaemia and pancytopenia. The spleen is enlarged but there is no correlation between the degree of anaemia and size of the spleen. Unlike patients with folate or cobalamin deficiency the MCV patient with hypersplenism do not have an markedly (>110fl) increased MCV.
  5. Anaemia of chronic disease: Anaemia of chronic disease may be seen in alcoholics because concurrent infection or inflammation.
  6. Haemolytic anaemia with spur cells: Patients with severe hepatocellular disease develop spur cells that result in haemolytic anaemia. This may be associated with increased jaundice and/or deteriorating liver function. Appearance of spur cells may be related to continued alcohol abuse in the presence of severe chronic liver disease. Transfused blood cells also become acanthocytic and are haemolysed. Abstinence from alcohol can eliminate/reduce spur cells. Spur cell anaemia has been cured by liver transplant.

 

The patient has a serum iron of 24 µg/dL the total iron binding capacity of 202µg/dL and a  transferrin saturation of 11.9%. The serum ferritin was 30 µg/L. The B 12 and folic acid levels were normal. The serum albumin was 3.2g/dL. The AST, ALT, prothrombin time and bilirubin were normal.

The patients was diagnosed to have iron deficiency. An upper gastrointestinal endoscopy showed gastro-oesophageal varices. Colonoscopy did nor show any cause of bleeding. A diagnosis of iron deficiency anaemia was made, iron supplementation given and varices banded.

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Anaemia of Renal Insufficiency


Richard Bright discovered the relationship of renal failure and anaemia in 1836. Anaemia of renal insufficiency is mainly results from decreased erythropoietin production and impaired supply of iron to erythroid precursors. Anaemia results in fatigue, cognitive dysfunction and cardiovascular consequences and increased cardiovascular mortality. Correction of anaemia decreases LVH, LVH related hospitalizations and mortality of cardiovascular disease. Without erythropoietin supplementation only 2% (Int J Artif Organs 1981; 4:277-9) needing haemodialysis have a hematocrit of >0.4. Availability of erythropoietin and the use of parental iron has reduced the prevalence of anaemia in patients with renal failure.

Pathogenesis of Anaemia of Renal Insufficiency

Anaemia associated with renal insufficiency results from decreased erythropoietin and iron availability.

Erythropoietin, produced by the kidney, is essential for erythropoiesis (see Erythropoietin and Erythropoietin Receptor Signalling). Renal insufficiency results in decreased renal mass and consequently in decreased erythropoietin production. Erythropoietin levels in patients with renal failure are normal or slightly elevated, but they are 10-100 times lower than a normal individuals with similar levels of anaemia. Decreased erythropoietin hampers erythropoiesis contributing to anaemia (no 1 in figure 1). Erythropoietin supplementation corrects anaemia in most but not all patients.

Three other causes of anaemia have been identified in patients with renal insufficiency. These are

  1. Impaired supply of iron
  2. Folate deficiency due to losses in dialysis
  3. Aluminium intoxication resulting in microcytic hypochromic anaemia

Folate deficiency and aluminium intoxication are of historical importance. Current management of dialysis patients includes folate supplementation and measures to prevent aluminium intoxication. Impaired iron supply to erythroid precursors remains the main cause of anaemia that does not respond to erythropoietin.

Iron is a component of heme (see heme synthesis). Patients with renal insufficiency have decreased iron availability from blood loss, impaired iron absorption and inability to use body iron stores (functional iron deficiency)

Causes of blood loss in patients with renal failure include (2 in figure 1)

  1. Gastrointestinal blood loss due to uraemia induced platelet dysfunction
  2. Blood loss due to dialysis
  3. Iatrogenic blood loss due to investigations (Transfus Med 2009; 19;309-14)

Iron supply to the erythroid precursors is also limited by impaired absorption (3 in figure 1) and a functional iron deficiency (4 in figure 1). Hepcidin plays a central role disrupting iron supply in patients of renal insufficiency. It reduces iron absorption in the gut and hampers the release of macrophage iron. The latter results in a phenomena called as functional iron deficiency i.e. diminished iron availability despite adequate iron stores. Hepcidin levels are increased from increased production because of inflammation and decreased elimination as a result of falling GFR. Infections, exposure of leucocytosis to foreign surfaces during dialysis and from the underlying cause of renal insufficiency are the sources of inflammation.

Clinical Features

The degree of anaemia co-relates with the degree of impairment of renal failure. Anaemia is rarely observed in patients with creatine clearance of greater than 45ml/1.72m2. This corresponds to a serum creatinine of 2-2.5mg/dL.  The anaemia is mild to moderate with the haematoctit stabilizing between 15-30%. Anaemia is less severe in polycystic kidney disease and to a lesser extent in hypertension. It may be more severe in diabetics. The presence of severe anaemia is an indication for evaluation for another cause of anaemia.

Signs and symptoms are those of anaemia and the underlying disease causing renal failure.

Diagnosis

A complete haemogram should be performed in all patients with chronic renal insufficiency at diagnosis. The diagnosis is made by the presence of a mild to moderate normochromic normocytic anaemia, presence of renal insufficiency and the absence of other causes of anaemia. Macrocytosis may be seen. The investigations that are usually performed in a patients with suspected anaemia of renal insufficiency include

  1. Complete haemogram with erythrocytes indices to determine severity of anaemia and to exclude co-existing diseases like iron deficiency and aluminium intoxication (microcytosis) or Folic acid/vitamin B12 deficiency (macrocytosis).
  2. The reticulocyte counts are normal but may rise with azotaemia
  3. Serum iron, total iron-binding capacity, percent transferrin saturation and serum ferritin need to be performed to asses the iron stores and iron delivery

Despite the fact that there is a relatively deficiency of erythropoietin, erythropoietin levels are not useful in the diagnosis of anaemia of renal insufficiency. The bone marrow tends to be moderately hypercellular with a slight erythroid hyperplasia.  A bone marrow aspiration is not necessary for diagnosis.

Treatment

The treatment of anaemia of renal insufficiency in transplant ineligible patients consists of erythropoiesis stimulating agent (ESA), iron and blood transfusion. Transplant when indicated cures anaemia in 80% of the patients. Most authorities define anaemia as a haemoglobin of 13-13.5g/dL in men and less than 12g/dL in women.

Iron therapy

All patients with chronic renal insufficiency need iron supplementation. The route of supplementation may be oral or intravenous. Severity of anaemia, patients preference and adherence and previous experience with that route iron therapy are few of the factors determining the choice. In a meta-analysis of oral iron vs. parental iron, parental iron raised the concentration of haemoglobin by >1g/dL more often than oral iron. The risk of hypotension was higher and gastrointestinal side effects lower with parental iron (Am J Kidney Dis. 2016 Nov;68(5):677-690). As the safety of intravenous iron preparation has increased so has their use. Many trials comparing oral with intravenous iron therapy have shown a better response with intravenous iron. However intravenous iron therapy has not been show to be superior in some trials (Clin J Am Soc Nephrol. 2016 Jul 7; 11(7)).

Erythropoiesis Stimulating Agenst (ESA)

ESA are indicated in patients who have adequate iron reserves. These are patients with transferrin saturationis >25 percent and ferritin >200 ng/mL. ESA should be used in patients with iron deficiency (actual or functional) after iron replenishment. Two ESAs available are erythropoietin and darbepoietin. Treatment with ESA results in improved quality of life, improved cognitive function and reduces left ventricular hypertrophy. The target of therapy is to increase the haemoglobin to 11-12g/dL. Higher targets are associated with more side effects. The rise is typically achieved in 6-8 weeks of therapy. Erythropoietin is administered in a dose of 100-150 units every week. Hypertession is seen in about 35% of the patients. Darbepoietin as administered in a dose 0.45 μg/kg/week for patients on dialysis.

Erythropoietin resistance is failure to respond to erythropoietin. The causes of erythropoietin resistance include inadequate iron availability (decreased reserves and/or functional iron deficiency) inadequate dialysis, marrow fibrosis associated with secondary hyperparathyroidism, folate deficiency, aluminium intoxication and co-existing inflammation. Dialysis should reduce blood urea to less than 35% to allow for optimal erythropoietin action.

 

Renal replacement therapy

Renal Allograft: Renal allograft is effective correction of anaemia in 80% of the patients. The rise is seen in 8-10 weeks. About 20% of the patients may get post-transplant erythrocytosis. The causes of failure of haemoglobin to rise after transplant include hemorrhage, intense immunosuppression or graft rejection

Dialysis: Dialysis has a small effect on the anaemia presumably by clearance of inhibitors. Peritoneal dialysis (PD) is more effective than haemodialysis. Reason a higher efficacy of PD is more effective in unknown but more effective removal of middle molecules (500-1500kD) and lesser of inflammation compared to HD may explain the higher haemoglobin in patients with on PD.

 

 

Anaemia with Thrombocytosis


A 49 year old woman presented with weakness and fatigability. On examination, other than pallor of the skin and mucosa there was no other finding.  A haemogram was done that showed a haemoglobin: 6.7g/dL, leucocyte count: 9.1 X 109/L and a platelet: 664 X 109/L.

Anaemia and thrombocytopenia is a feature of

  1. Myeloproloferative neoplasm
  2. Chronic inflammation
  3. Underlying malignancy (Paraneoplastic)
  4. Iron deficiency

A haemogram from a automated haematological counter hides a lot of information. Before more investigations are done it is important to assimilate all the information in the haemogram. The haemogram in the above listed conditions shows:

  1. Myeloproliferative Neoplasm: The myeloproliferative neoplasm are diseases characterised by proliferation of bone marrow. They are distinct from acute leukaemia. According to the 2016 WHO classification myeloproliferative neoplasm include chronic myeloid leukaemia (CML), chronic neutrophilic leukaemia (CNL), polycythaemia vera (PV), progressive myelofibrosis (PMF), essential thrombocytosis (ET), chronic myeloproliferative neoplasm unclassified (CMPN-U) and chronic eosinophilic leukaemia (CEL).  Myeloproliferative diseases associated with anaemia and thrombocytosis are CML, prefibrotic phase of PMF and CMPN-U. Haemogram of patients with myeloproliferative diseases shows leucocytosis with presence of immature leucocyte forms. This is most pronounced in patients with CML. In fact leucocytosis with the presence of immature leucocyte forms is the dominant feature of the haemogram of patients with CML. Anaemia of myloproliferative is normocytic and normochromic.
  2. Chronic Inflammation and Paraneoplastic Diseases: Anaemia and thrombocytosis can also be seen in patients with chronic inflammation and as a paraneoplastic finding. An occasional immature leucocyte form may also be seen in these conditions. This picture may be indistinguishable from that myeloproliferative diseases other than CML. The anaemia is normocytic and normochromic. When the chronic disease or neoplasm is associated with blood loss as may be the case in cancers of the gastrointestinal tract or inflammatory bowel disease, microcytosis due to a coexisting iron deficiency may be seen.
  3. Iron Deficiency: Iron deficiency is associated with microcytic hypochromic anaemia. The degree of microcytosis co-relates with the degree of iron deficiency. The leucocyte counts depends on the cause of iron deficiency. Commonly the leucocyte is normal or slightly decreased. Patients who have iron deficiency because of blood loss due to an inflammatory condition may have leucocytosis. Iron deficiency from blood loss due to helmethiasis may cause eosinophilia.

The differential leucocyte count showed 67% polymorphs, 27% lymphocytes, 2% monocytes and 4% basophils. The erythrocyte indices were MCV 61fl, MCH 15.3pg and MCHC 24.9g/dL. The red cell distribution width was 28.5%. The peripheral smear showed hypochromia, microcytosis, anisocytosis and poikilocytosis.

Of the causes of anaemia and thrombocytosis listed above only iron deficiency is characterised by hypochromic microcytic anaemia. Iron deficiency is also characterised by anisocytosis and poikilocytosis. This manifests as increased red cell distribution on the haemogram.

The serum iron was 27.9 µg/dl, the total iron binding capacity 488 µg/dl with a transferrin saturation 5.7%. The serum ferritin was 8.53 ng/ml. The haemoglobin electrophoresis showed a haemoglobin A2 of 2.8%, the HbA 96% and haemoglobin F 1.2%.

Iron deficiency is diagnosed by documenting low body iron stores and/or impaired iron delivery of iron to the erythroid precursors. The gold standard for depletion of iron stores is absence of stainable iron in the bone marrow. Serum ferritin accurately reflects body iron stores. It has become the preferred method to demonstrate depletion of body iron stores because of the invasive nature of bone marrow aspiration. Levels less than 15ng/ml strongly suggest iron deficiency. Serum ferritin is specific but not sensitive for iron deficiency. Its has a sensitivity of 59% if the cutoff is 15ng/mL and 75% if the cutoff is less than 16ng/ml. The low sensitivity makes the test of limited value to exclude iron deficiency. Ferritin in an acute phase reactant. It has a limited value in the presence of inflammation.

Unlike low serum ferritin, low serum iron is of limited value in diagnosis of iron deficiency. Iron delivery to the haemoglobinizing erythroid precursors is a function of transferrin saturation rather than the serum iron levels. One can have a low serum iron and a low total iron binding capacity as may be seen in anaemia of chronic disease and yet have a normal transferrin saturation. Such patients do not benefit from iron supplementation. Patients with iron deficiency have a low transferrin saturation indicated impaired iron delivery to the developing erythroid cells. Lower the iron saturation higher the probability of iron deficiency being present. Patients are considered to be iron deficient if the transferrin saturation is less than 16%. This patient had a transferrin saturation of 5.7% and a serum ferritin of 8.63ng/ml along with microcytic hypochromic anaemia. A diagnosis of iron deficiency anaemia was made.

The diagnosis of iron deficiency is incomplete without diagnosing the cause of anaemia. Iron deficiency in a 49 year old woman frequently is a result of blood loss that is often menstrual.  This woman had attained menopause and is being evaluated for a gastrointestinal blood loss.

Heme Synthesis


Heme, a porphyrin, is a co-factor in haemoglobin, myoglobin, cytochrome, catalase, heme peroxidase, and endothelial nitric oxide synthase. It has a complex structure with four pyrrole rings with a ferrous iron in the centre that allows it to carry oxygen. The synthesis of heme takes place from glycine and succinyl CoA in eight steps and is extensively studied. Mutations in genes encoding for enzymes involved in heme synthesis result in porphyrias.

Steps in Heme synthesis

About 85% of the heme is synthesised in the developing erythroid cells and almost all the remaining is synthesised in the liver. The control of synthesis differs in erythroid and non-erythroid cells reflecting the exceedingly high heme requirement of the former for haemoglobin synthesis. Heme synthesis takes place in the mitochondria as well as cytosol. The first step, formation of δ-aminolevulenic acid, takes place in the mitochondrial matrix. The next few steps take place in the cytosol. The heme precursor, corpoprophyrinogen III, returns to the mitochondria, is converted to protoporphyrin IX and iron incorporated. The steps in heme synthesis are as follows

  1. Synthesis of δ-aminoleuvelinic acid: Synthesis of δ-aminoleuvelinic acid (ALA) from glycine and succnyl CoA catalysed by ALA synthase (ALAS) is the first step in the synthesis of heme. This is a rate limiting step. ALA synthase is encoded by two genes ALAS1 (OMIM 125290) and ALAS2 (OMIM 301300). ALAS2 codes for the erythroid ALAS and ALAS1 for the non-erythroid (housekeeping) ALAS. The gene ALAS1 is located on chromosome 3p21.1. The product has 12 exons and undergoes is alternate splicing to yield two distinct forms, isoform 1 (640 amino acids) and isoform 2 (657 amino acids). The erythroid specific gene (ALAS2) on X chromosome at Xp11.21. It has 12 exons and also undergo alternate splicing to yield two forms, isoform b (587 amino acids), isoform c (574 amino acids). ALAS is synthesised in the cytosol and transported to the mitochondria. It has a short half life. Heme synthesis is consoled by regulating levels and activity of ALAS (discussed below).
  2. Synthesis of prophobilinogen: ALA moves to the cytosol and is dimerised to prophobilinogen by the action of prophobilinogen synthase (ALA dehydratase). The enzyme is a homo-octomer (made of eight similar units) and needs zinc. The gene (gene ALAD, OMIM 125270) encoding the enzyme is located at 9q32. It has 15 exons. Four isoforms from alternate splicing 361 amino acid, 344 amino acid, 321 amino acid and 304 amino acid are known.
  3. Synthesis of hydroxymethylbilane: Prophobilinogen is converted to hydroxymethylbilane by the action of hydroxymethylbilane synthase. This enzyme is also known as propohbilinogen deaminase. The gene (HMBS OMIM 609806) is located at 11q23.3, has 15 exons. Four alternately spliced forms with 361, 344, 321 and 304 amino acids are known.
  4. Synthesis of uroporphyrinogen: Hydroxymethylbilane is converted to enzymatically to uroporphyrinogen III as well as non-enzymatically to uroporphyrinogen I. The enzymatic conversion is catalysed by the enzyme uroporphyrinogen III synthase. Uroporphyrinogen III synthatase is encoded by a gene (UROS, OMIM, 606938) on 10q25.2-q26 that has 16 exons and encodes for a 265 amino acid protein.
  5. Synthesis of corpoporphyrinogen III: Uroporphyrinogen III is decrboxylated to corpoporphyrinogen III by uroporphyrinogen decarboxylase. The gene (UROD, OMIM 613521) for thes enzyme is at 1p34. It has 10 exons and encodes for a protein 367 amino acid long. This is the last step in the cytosol.
  6. Synthesis of protoporphrinogern IX: Coproporphyrinogen III is converted to propoporphyrinogen IX by a reaction catalysed by corpoporphyrinogen oxidase  in the mitochondria in an oxygen dependent reaction. The gene for corpoporphyrinogen oxidase (COPX, OMIM 612732) is at 3q11.2-q12.1 8 exons. The product has 454 amino acids.
  7. Synthesis of protoporphyrin IX: Propoporphyrin is the final product of the pathway into which iron is incorporated. Protoporphyrin IX is synthesised by the action of protoporphyrinogen oxidase. The gene (PPOX, OMIM 600923) for this enzyme is located at 1q22  and has14 exon. It encodes for a 477 amino acid enzyme.
  8. Synthesis of heme: Ferrochelatse (protoporphyrin ferrochelatase) catalysed the incorporation of iron into protoporphyrin IX. The gene (FECH, OMIM 612386) for ferrochelatse is located at 18q21.31 and has 11 exons. It encodes for a 477 amino acid enzyme.

Control of heme sythesis

The rate limiting enzyme of heme synthesis is the synthesis of ALA. ALA synthase has a short half life. Heme synthesis is regulated  by controlling the levels and activity of ALA synthase.

  1. Inhibition of ALA synthase: ALA synthase is subject to feedback inhibition by heme and and it’s oxidation product hemin. ALA synthase is synthesised in the cytosol and transported to the mitochondrial matrix. In addition to being an inhibitor of ALA synthase hemin also inhibits the metochondrial transport of the enzyme.
  2. Promotion of ALA synthase activity: Cellular iron and factors promoting erythroid differentiation increase the synthesis of ALAS-2, the enzyme responsible ALA synthesis in erythroid cells. Erythroid specific factors like GATA-1 promote the transcription of the ALAS-2 gene. Untranslated portions of the ALAS-2 mRNA have iron responsive elements (IRE) that promote translation. The activity of ASLS in iron deficient cells is low.

Porphyrias

Porphyrias are inherited diseases resulting from a mutation of genes involved in heme synthesis. With one exception, X-linked porphyria that results from a gain of function mutation of ALAS synthase 2, porphyrias result from a partial deficiency of the enzymes involved in heme synthesis. Enzyme deficiency results in accumulation of substrates for the reaction catalysed by the enzyme encoded by the gene. Symptoms of porphyrias may be intermittant and/or chronic. The symptoms are diverse and include skin changes, photosensitivity, abdominal pain, muscle weakness, CNS disturbance, seizures, hyponatremia, discolouration of urine. Enzyme deficiencies associated with porphyrias as as follows:

  1. ALA synthatase 2: Gains of function mutation in X linked protoporphyria
  2. ALA dehydratase: ALA dehydrate deficient porphyria (ADP). Lead displaces zinc from binding sites inhibiting the function of the  with enzyme. In patients with tyrosinaemia type 1 Succinylacetone (4,6-dioxoheptanoic acid) accumulates in tyrosinaemia type I. It is structurally similar to ALA and a potent inhibitor of ALA dehydratase.
  3. PBG Deaminase deficiency results in acute intermittent porphyria
  4. Uroporphyrin III synthatase deficiency results in congenital erythrocytic porphyria
  5. Uroporphyrin decarboxylase deficiency results in porphyria cutanea tarde. All patients with porphyria cutanea trade do not have a mutation. Only type II has gene mutations. Types I and III are due to mulifactorial effects on the gene.
  6. Coproporphyrin III oxidase deficiency results in hereditary coproporphyria
  7. Protoporphyrin oxidase results in varigate porphyria
  8. Ferrochalase results in erythropoietic porphyria

Further Reading

Porphyrin and Heme Metabolism
Erythroid Heme Biosynthesis and Its Disorders (doi:  10.1101/cshperspect.a011676)

 

Evaluation of Splenomegaly


The spleen is a secondary lymphoid organ that lies in intraperitoneally in the left hypochondrium, abuting the diaphragm. It spans from the 9th to 11th rib and weighs between 150-200g. Spleen is supplied by the splenic artery and drains into portal circulation via the splenic vein. It is a part of reticuloendothelial system, immune system and is a site of in utero haematopoiesis. The spleen is enlarged in a diverse set of disease of the above mentioned  systems and in portal hypertension.

Normal Functions of the Spleen

The normal functions of the spleen include

  1. Reticuloendothelial functions: The spleen as a component of the reticuloendothelial system is involved in clearing the blood of ageing or damaged erythrocytes, antibody coated cells and opsonised bacteria. It also removes particles from red cells. The spleen ensures that the red cell in circulation have adequate deformability for passage through microcirculation.
  2. Immune Functions: The spleen is a part of the immune system and plays a role in mounting the immune response . Splenectomy increases the risk of infections particularly with capsulated organisms (see Overwhelming Post-Splenectomy Infection (OPSI)).
  3. Haematopoiesis: Spleen is the site for haematopoiesis in utero. In extrauterine life spleen can become a site of haematopoiesis in disease.

Palpating the Spleen

  1. Palpation of the spleen should start from the right iliac fossa. If this is not done there is a risk of missing a massively enlarged spleen.
  2. Move towards the left costal margin in a direction perpendicular to the margin. Move with each breath. At every position ask the patient to take a deep breath. The tip of the spleen will hit your palpating finger.
  3. If the spleen does not hit your finger move your palpating finger to a position closer to coastal margin, ask the patient to take a deep breath and repeat the procedure described above till your finger hits the costal margin.
  4. If the spleen is felt measure the perpendicular distance between the tip and the left coastal margin. Also note the texture and presence of tenderness.
  5. If the spleen is not felt repeat the procedure with patients lying on right side.
  6. Large spleen can rupture with aggressive palpation. The spleen lies directly under the anterior abdominal wall. One does not need to be aggressive.

Causes of Splenomegaly

The spleen enlarges from the left coastal margin in the direction of the umbilicus. It needs to enlarge 2-3 times before it is palpable. Splenomegaly may be caused be increase in portal venous pressure, infiltrative conditions or when the spleen function needs to increase. Clinically it is useful to classify splenomegaly by size. Massive splenomegaly is enlargement of the spleen beyond the umbilicus. The causes of massive splenomegaly include

  1. Malignant: Chronic myeloid leukaemia, Idiopathic myelofibrois, hairy cell leukaemia, splenic marginal zone lymphoma, chronic lymphocytic leukaemia, prolymphocytic leukaemia
  2. Infections: Tropical splenomegaly, AIDS with Mycobacterium avium complex infections, Kala-azar (visceral leishmaniasis)
  3. Others: β-Thalassaemia major and intermedia, Extrahepatic portal venous obstructions,megaloblastic anaemia, diffuse splenic haemagiosis

The causes of splenomegaly include the above and the following

  1. Portal Hypertension: Cirrhosis, Budd-Chairy syndrome, splenic vein thosmbosis, congestive heart failure, hepatic schistosomiasis
  2. Increased splenic function:
    1. Increased functional demands: Haemolytic anaemia commonly hereditary spherocytosis, autoimmune haemolytic anaemia, β-thalassaemia, early sickle cell anaemia, sickle cell β-thalassaemia,
    2. Infections:
      1. Bacterial: Septicaemia, bacterial endocarditis, splenic abscess, brucellosis, tuberculosis, AIDS with Mycobacterium avium complex infections, secondary syphilis
      2. Viral: Viral hepatitis, infectious mononucleosis, cytomegalovirus,
      3. Parasitic: Malaria , Kala-azar (visceral leishmaniasis), Trypanosomiasis,
      4. Fungal: Histoplasmosis
    3. Immune Disorders:
      1. Autoimmune diseases: Rhumatoid arthritis (Felty’s syndrome), systemic lupus erythrmatosis
      2. Other immune disorders: Immune haemolytic anaemia, immune neutropenia, drug reaction, serum sickness, sarcoidosis
      3. Haemophgocytic lymphohistiocytosis
  3. Infiltrations
    1. Haematological Malignancy:
      1. Myeloid: Chronic myeloid leukaemia, myeloproliferative disease, idiopathic myelofibrosis, polycythaemia vera
      2. Lymphoid: Acute lymphoblastic leukaemia, hairy cell leukaemia, chronic lymphocytic leukaemia, prolymphocytic leukaemia, splenic marginal zone lymphoma, angioimmnoblastic T cell lymphoma
      3. Other: Histiocytosis X, eosinophilic granuloma
    2. Storage disorders:Gaucher disease, Niemann-Pick, Tangier disease, mucopolysachroidosis
    3. Other Infiltrations: Amyloid
  4. Others: Iron deficiency anaemia

 

History and Physical Examination

  1. Fever: Fever is a feature of splenomegaly due to infections, inflammations or malignancy, particularly haematological malignancy. Usually the fever is low grade. High grade fever suggests splenic abscess.
  2. Painful splenemegaly: The nature of pain associated with splenomegaly varies with the cause of splenomegaly.
    1. An enlargement spleen from any cause can cause a dragging pain in the left upper quadrant.
    2. Acute pain left upper quadrant pain is a feature of is a feature of splenic infarct and splenic abscess. Sickle Cell anaemia is associated with small fibrotic spleen because of repeated splenic infarcts. Early in disease the spleen enlarges. Patients may present with acute pain from splenic infarcts. Enlarged spleen from any cause is predisposed to infarction. Acute pain in the left upper quadrant is also a feature of acute splenic abscess.
    3. Splenic vein thrombosis can cause splenomegly and pain in left upper quadrant or epigastric region. It may also cause generalised abdominal pain.
    4. Pancreatitis presents with abdominal pain and can cause painful splenomegaly secondary to splenic vein thrombosis.
    5. Alcohol induced pain is an uncommon but unique feature of Hodgkin lymphoma. Spleen is a common site of involvement by Hodgkin lymphoma. Such patients may have alcohol induced pain in an enlarged spleen.
  3. Pallor: Pallor in a patient with splenomegaly suggests a diagnosis of haemolytic anaemia, haemolymphatic malignancy and infective endocarditis.
  4. Clubbing: Clubbing with splenomegaly is a feature of infective endocarditis and cirrhosis of the liver.
  5. Skin rash: Skin rash in a patient with splenomegaly is seen in systemic lupus erthomatosis, infective endocarditis, lymphoma (angioimmuniblastic T Cell lymphoma, mycosis fungiodes, skin involvement with lymphoma) and drug reaction.  Each of these conditions have a distinct type of rash.
  6. Skin Pigmentation: Hyperpigmantation suggests be seen in hemachromatosis or megaloblastic anaemia. The patients with megaloblastic anaemia may also have knuckle pigmentation.
  7. Jaundice: Jaundice with enlarged spleen is a feature of haemolytic anaemia. The jaundice is usually achloruric. Patients with haemolytic anaemia are predisposed to gallstones. Obstruction of the biliary system from a calculus dislodged from the gall bladder can cause obstructive jaundice with abdominal pain and signs of acute inflammation. Splenomegaly with jaundice is a feature of advanced cirrhosis. Patients with advanced cirrhosis almost always have ascites.
  8. Lymphadenopathy: The enlargement of lymph nodes and spleen is a feature of lymphoid malignancies or diseases that stimulate the lymphoid systems viz. infections and autoimmune diseases and lymphoid malignancy.
  9. Joint symptoms: Arthropathy with splenomegaly suggests the diagnosis of rheumatoid arthritis, systemic lypus erythrmatosis or haematochromatosis.
  10. Oral symptoms: infectious mononucleosis is charecterized by pharyngitis and generalised lymphadenopathy. Bleeding gums and/or gum hypertrophy suggests a diagnosis of leukaemia. Lymphoma can cause tomsillar enlargement. Amyloid is charectetized by macroglossia.
  11. Evidence of Portal Hypertension and Liver Cell Failure: Patients with portal hypertension often have history of haemetemesis. Examination may reveal periumbilical veins (capital medusae), anterior abdominal or flank veins. Patients with evidence liver cell failures with portal hypertension (e.g. jaundice, ascites, spider angiomas, asterxis etc. see Portal Hypertension) have cirrhosis. When the jugular venous pressure is high a diagnosis of congestive cardiac failure should be considered.

Laboratory Evaluation

Haemogram; The haemogram is the most important laboratory test in evaluating a patient with splenomegaly. The significance of findings on haemogram is described in the table below.

Haemogram Finding Conditions
Pancytopenia Hypersplenism, Lymphoma (splenic marginal zone lymphoma), Hairy cell leukaemia, Myelofibrosis, systemic lupus erythrmotosis
Neutrophilic Leucocytosis Acute infections, inflammation
Leucocytosis with premature white cells Chronic myeloid leumaemia, Myeloproliferative disease, Myeloproliferative/Myelodysplastic overlap, Acute lymphoblastic leukaemia
Leucoerythroblastic anaemia Idiopathic myelofibrosis, Bone marrow infiltration
Polycythaemia Polycythaemia vera
Atypical Lymphocytes Infectious mononucleosis
Thrombocytosis Myeloproliferative disease (Chronic myeloid leukaemia, idiopathic myelofibrosis, polycythaemia vera), chronic infections like tuberculosis
Parasites Malaria, bartonelosizs, babesiosis

Other investigations are dictated by the clinical presentations. Commonly performed investigations include biochemistry, microbiology, echocardiography, endoscopy and biopsy of any lymph node or any other mass. Other investigation may be performed as indicated

Imaging

Imaging is an important aspect of evaluation of the spleen but is beyond the scope of this article. Several good reviews exist e.g Singapore Med J 56(3):133-144.

Oral Iron Therapy


Iron deficiency anaemia is treated by iron supplementation that may be administered orally or parenterally.  Oral iron absorption is inefficient, is interfered by food and is associated with high incidence of gastrointestinal adverse effects. About 17% of the world population is estimated to be suffering from iron deficiency. Iron deficiency is more common the poorer regions of the world. These regions have limited resources allocated for healthcare. Oral iron is inexpensive and convenient to administer making it the modality of choice for initiation of treatment of iron deficiency. The availability of safer parenteral iron preparations that can replete the iron deficit in one dose has reduced the threshold of switching a person intolerant to iron to parenteral iron.

Oral Iron Absorption

Dietary iron may be heme iron or non-heme iron. Heme iron is absorbed after oxidation to hematin. The absorption of heme iron is more efficient. Dietary non-heme iron is present in the ferric state. Ferric iron is insoluble and needs to be reduced to ferrous iron. Gastric acidity aids this conversion. Medicinal iron is most often administered in the ferrous state. Ferrous iron tends to oxidize to ferric iron at physiological pH. Gastric acid lowers the pH and retards oxidation. The absorption of non-heme iron is aided by ascorbate, animal proteins, human milk, keto sugars, organics, amino acids that form soluble chelates and retarded by phytates present in grains and vegetables, dietary fibre, polyphemols present in tea, coffee and wine, phosphates and phosphoproteins present in egg yolk, bovine milk, calcium and zinc. For a detailed discussion on iron absorption see intestinal iron absorption. Preparations containing iron in the ferric state have a 3-4 fold lower bioavailability than ferrous iron preparations. Ferric iron is insoluble in the alkaline medium of the duodenum and needs to be converted to ferrous iron (ScientificWorldJournal. 2012; 2012: 846824).

Oral Iron Preperations

Oral iron preparations may be heme or non-heme. Heme iron is available as heme iron polymer. Non-heme iron may be in the ferrous or ferric form. Carbonyl is pure iron prepared from the decomposition of iron pentacarbonyl. The preparations are listed in the table below.

 

Preparations Iron Content
Ferrous Sulfate, anhydrous 30%
Ferrous Fumarate 33%
Ferrous Sulfate 20%
Ferrous carbonate, anhydrous 48%
Ferrous Gluconate 12%
Ferric Ammonium Citrate 18%
Ferric bisglycinate 20%
Ferric pyrophosphate 12%
Carbonyl iron ~100%
Heme-iron peptide 100%
Polysaccharide iron complex 100%

Indications of Oral Iron Therapy

Oral iron is indicated for prevention and treatment of iron deficiency anaemia. The rate of iron delivery is insufficient to provide iron when erythropoiesis is stimulated by erythrocyte stimulating agents like erythropoietin and darbepoetin. Oral iron should not be used for such patients.

Trial of Oral Iron Therapy

Serum ferritin is an indicator of total body iron. It is also an acute phase reactant. Low ferritin indicates iron deficiency. The traditional cutoff is 12ng/mL. At this cutoff the sensitivity of ferritin for the diagnosis of iron deficiency anaemia is only 25%. The sensitivity can be increased to 92% with a positive predictive value of 83% if a cutoff of 30ng/mL is used. A trial of oral iron may be given if other causes of anaemia are excluded.

Contraindications to Oral Iron Therapy

  1. Primary hemachromatosis: Primary hemochromatosis is a is absolute contraindication
  2. Peptic ulcer, regional enteritis, or ulcerative colitis can be exacerbated by oral iron.
  3. β-Thalassaemia trait is a relative contraindication. Some patients may develop iron overload. Patients should be given iron only if iron deficiency is established by laboratory investigation.

Failure of Oral Iron Therapy

  1. Failure to take prescribed medication: Oral iron therapy causes gastrointestinal adverse effects in a large proportion patients that are severe enough in some to discontinue therapy. A detailed history must be taken to ascertain that the patient has taken the prescribed dose.
  2. Incorrect or incomplete diagnosis: Iron deficiency anaemia is hypochromic microcytic (see Evaluating Anaemia). Other diseases that result in hypochromic microcytic anaemia are thalassaemia and anaemia of chronic disease. Both are common and can both be confused with iron deficiency as well as co-exist with iron deficiency. Thalassemia trait affects about 1.5% of the world population. About 1.4% of the population is estimated to have anaemia due to infection, inflammation or chronic renal disease (https://dx.doi.org/10.1016%2FS0140-6736(15)60692-4). Incidental occurrence of iron deficiency with thalassaemia trait or anaemia of chronic disease will result in an incomplete response to iron supplementation. Some inflammatory conditions e.g. ulcerative colitis cause blood loss. Blood loss may be seen due to use of non-steroidal inflammatory agents in patients with autoimmune arthritis. Anaemia in these patients shows an incomplete response to iron supplementation because part of the anaemia results from chronic inflammation.
  3. Insufficient amount or inappropriately taken oral iron: The ideal dose is 200mg of elemental iron taken 2 hours before or 1 hour after food. Food interferes with iron absorption but also relieves gastrointestinal adverse effects. Gastrointestinal adverse effects are related to dose. Prescriptions of oral iron may have an insufficient dose or may be administered after food to reduce gastrointestinal adverse effects. This results in an inappropriate haemoglobin response.
  4. Iron demand exceeding intake: Iron demand may exceed supply if there is continued blood loss or in patients where erythropoiesis is stimulated with an erythropoiesis stimulating agent like erythropoietin or darbepoietin. In both these situations the rate of oral iron absorption limits iron availability. These patients need intravenous iron.
  5. Malabsorption of iron: Food interferes with oral iron absorption. Ferrous iron is rapidly oxidised to ferric iron at physiological pH. Gastric acid reduces ferric iron to ferrous iron. Proton pump inhibitors, H2 antagonists, antacids and gastrectomy reduce acidity and can interfere with iron absorption. Iron malabsorption may be seen as part of a malabsorption syndrome. Iron deficiency refractory to iron is rare. Iron refractory iron deficiency anaemia is a disorder resulting from mutations in the TMPRSS6. This mutations results in increase hepcidin production which is sensed by the body as an iron repeated state. Iron is not absorbed despite iron deficiency. The patients do not respond to oral iron and shows a partial response to parenteral iron.

 Interactions

  1. Interaction of iron with food: The absorption of non-heme iron is affected by food (See Intestinal Iron Absorption).
    1. Foods enhancing iron absorption: Ascorbate, animal proteins, human milk, keto sugars, organics, amino acids that form soluble chelates with iron enhance absorption of non-heme iron.
    2. Inhibiting iron absorption: `Inhibitors of absorption of non-heme iron include
      1. Phytates present in grains and vegetables
      2. Dietary fibre
      3. Polypohenols present in tea, coffee and wine,
      4. Phosphates and phosphoproteins present in egg yolk, bovine milk
      5. Calcium and zinc.
  2. Drug-Iron interactions
    1. Iron decreases the absorption of ACE inhibitors, bisphosphonates, levodopa, levothyroxine, penicillamine, quinolone and tetracyclines
    2. The absorption of iron is decreased by drugs that reduce gastric pH. These include H2 antagonists(Cimetidine, ranitidine, famotidine), proton pump inhibitors (omeprazole, pantoprqzole, esomeprazole, lansoprazole, rabeprazole, etc), antacids and cholesterol lowering agents (Cholestyramine and Colestipol).

Dose

  1. Children: 3–6 mg/kg daily in 3 divided doses.
  2. Adult: Usual therapeutic dosage: 50–100 mg 3 times daily but a dose of 200mg produces the maximal results. A smaller dosages (e.g. 60–120 mg daily) may be given if patients are intolerant of oral iron, but response in such patients takes a longer time.

Side Effects Of Oral Iron

  1. Gastrointestinal: The commonest adverse effects of iron are gastrointestinal symptoms, including heartburn, nausea, abdominal cramps, diarrhoea or constipation. These may be seen in up to a fifth of the patients. They can be reduced by decreasing the dose or taking iron after food. Taking iron with food can reduce the absorption by about 50%. Enteric coated preparation decrease the side effects by delaying the release of iron. Delaying release may bypass the duodenum that is the site of absorption of iron. The decrease in absorption is particularly marked in patients with aclorhydria as they can not dissolve the enteric coating. The stool of patients taking iron supplements may be discoloured black or green.
  2. Discolouration of teeth: Iron syrups may cause staining to teeth.
  3. Iron overload: Iron overload from oral iron therapy is rare. It has been described in patients with hemachromatosis and chronic haemolytic anaemias.
  4. Iron Poisoning: Iron poisoning usually occurs in children, particularly those younger than 5 years of age, because of accidental ingestion of medicinal iron. Children are likely to ingest these believing them to be candies.

Clinical Features of Megaloblastic Anaemia


Megaloblastic anaemia is a macrocytic anaemia resulting from the deficiency of vitamin B12 or folic acid characterised by the presence of megaloblasts in the bone marrow. It has haematological and neurological manifestations. The haematological manifestations are seen with folate as well as vitamin B12 deficiency. Folate deficiency in adults does not affect the nervous system.

Cobalamin deficiency is slow and “pure”. Folate deficiency is rapid and “impure”. Deficiecy of vitamin B12 occurs because of loss of intrinsic factor resulting in an isolated defect of B12 absorption. No other nutrients are affected. The body stores of B12 can last months. This results in B12 deficiency being a slow and “pure” deficiency. Symptoms come on slowly, over months. Folate deficiency evolves relatively quickly and is most commonly because of alcoholism or malabsorption. It is associated with other deficiencies and is rapid and “not pure”.

 

Manifestationf o megaloblastic anaemia

Figure 1. Clinical Manifestations of Megaloblastic Anaemia

Haematological Manifestations

Haematological changes resulting from vitamin B12 deficiency and folate deficiency are indistinguishable. Megaloblastic anaemias are macrocytic anaemia but macrocytosis is not specific to megaloblastic anaemia. It is however exceptional for other diseases characterised by macrocytosis to have an mean capsular volume (MCV) > 110fl.  This value can considered the threshold above which an anaemia is unlikely to be anything other than megaloblastic anaemia.

The earliest change in a megaloblastic anaemia is macrocytosis. This precedes changes in erythrocyte indices. Changes in mean capsular haemoglobin (MCH) follow and then the MCV rises. Haemoglobin usually falls after the MCV increases to >97 fl. As the severity of anaemia increases the peripheral smear shows aniscytosis and poikilocytosis, nucleated cells, Howell-Jolly bodies and Cabot’s ring. Microcytes and erythrocyte fragments that represent dyserythropoiesis may be seen. Polychromasia is absent and this distinguishes megaloblastic anaemia from haemolytic anaemia.

The term megaloblatic anaemia is a misnomer. The disease is actually a panmyelosis.  Erythroid, myeloid and megakaryocytic series are affected. Thrombocytopenia and leucopenia (neutropenia and to a lesser extent lymphopenia) usually occur late in the course. It is uncommon for patients with mild anaemia to have platelets and neutrophils but occasionally changes in leucocytes and/or platelets may dominate.

Iron deficiency or β-thalassaemia trait result in microcytosis and hypochromia and may incidentally co-exist with megaloblastic anaemia. Co-existence of either of these diseases with megaloblastic anaemia may mask macrocytosis of megaloblastic anaemia. Presence of hypersegmented neutrophils in a patients with normocytic normochromic anaemia should raise the suspicion of a megaloblastic anaemia co-existing with Iron deficiency or β-thalassaemia trait.

Neurological Manifestations

Cobalamine deficiceny causes neurological dysfunction. Folate deficiency causes symptoms only in children. Children with inborn errors of folate metabolism may have myelopathy, brain dysfunction and seizures.

The neurological manifestations of B12 deficiency are a result of a combination of upper motor neuron manifestations from subacute combined degeneration of the spinal cord, sensory and lower motor neuron manifestations from peripheral neuropathy and neurophychiatratic manifestations. Subacute combined degeneration of the spinal cord (SACD) is a degerative disease of the spinal cord involving the posterior and lateral column (corticospinal and spinoceribellar tracts) that starts in the cervical and the thoracic region.

The earliest neurological manifestations are impaired sense of vibration and position and symmetric dysesthasia that involve the lower limb. This is frequently associated with sensory ataxia. With progression spastic paraparesis develops. The patients have brisk knee reflexes, reflecting an upper motor neuron involvement and depressed ankle reflex, reflecting a peripheral neuropathy. Bladder involvement is unusual. Some patients may have optic atrophy.

Neuropsychiatric manifestation include memory loss, depression, hypomania, paranoid psychosis with auditory and visual hallucinations.

Other manifestations

Skin and nails can show pigmentations. Mucosa of the villi undergoes megalobkastic change resulting in temporary malabsorption.

Response to therapy

Haematological Recovery

  • Day 1: Feeling better
  • Day2-3: Reticulocytosis appears
  • Day 7-10: Peak retuculocytosis
  • Day 15 onwards: Neutrophilic hypersegmentation disappears
  • Day 56 (8 weeks): Blood counts become fully .normal

Neurological Recovery

Neurologic improvement begins within the first week also and is typically complete in 6 weeks to 3 months. Its course is not as predictable as hematologic response and may not be complete.