Lab case 424 interepretation

Answers:

Hb = 115 g/L, that is mild anaemia. (Remember, anaemia happens when blood cells don’t have enough haemoglobin or there is not enough red blood cells).

RCC (red cells count) = 4.3, that is just within the normal range for men, towards the low side.

PCV (packed cell volume/Haematocrit) = 0.345, that is low for a male.

Normal PCV value for a male 0.407 – 0.503 (These values are different between different labs and different references). Low PCV value usually reflects haemodilution.

M.C.H.C = 333, that is with in the normal range (320 – 360 g/L).. Accordingly this patient has normochromic anaemia.

MCV = 80 fL, that is with in normal range. Normal MCV value is between 80 – 100 fL. (Differ between different labs).

So this patient has mild normochromic, normocytic anaemia.

MCH = 26.7 pg, that is within the normal range. Normal range is between 26 and 33 picograms of haemoglobin per RBC.

RDW = 15%, this is within normal range. Normal range is between 12 – 15%

Platelets count = 86 (That is 86000 per microliter of blood), that is moderate thrombocytopenia.

Thrombocytopenia is caused by:

  • Increased platelets destruction (Immune and non-immune causes)
  • Decrease production
  • splenic sequestration

WBC = 5.7, this is within the normal range.

So looking at the haematology side of this question, this patient has mild normochromic, normocytic anaemia with moderate thrombocytopenia.

Looking at the biochemistry part,

Na = 126 mmol/L, that is moderate hyponatraemia.

K = 3.1 mmol/L, that is mild hypokalaemia.

Cl = 94 mmol/L, that is mild hypochloraemia.

With normal kidney function.

It is a good practice to always calculate the anion gap, in this case it is

AG = 126 – ( 94 + 22) = 10, that is normal.

The picture also fits with haemodilution.

This patient has isolated hyperbilirubinaemia. That is either due pre-hepatic cause (Haemolysis) or due to enzyme deficiency (Gilbert syndrome or Crigler-Najjar syndrome ). In case of haemolysis it is usually a new finding while enzyme deficiency causes are usually long standing. We can figure out that by looking at previous blood tests.

This patient had Malaria.

Tests for malaria should be requested for every traveller fever returning from endemic areas. (Infectious diseases that we need to test for are Dengue fever and Typhoid fever).

These blood tests findings are typical of malaria infection.

Reduced Hb is due to haemolysis of the RBC, it is also the cause of isolated. Malaria parasite infect red blood cells. At the end of that infection cycle, red blood cell ruptures.

The speculated mechanisms leading to thrombocytopenia in malara  are: (1-3)

  • Coagulation disturbances.
  • Splenomegaly.
  • Bone marrow alterations.
  • Antibody-mediated platelet destruction
  • Oxidative stress,
  • The role of platelets as cofactors in triggering severe malaria

Hyponatraemia is malaria is common and is associated with preserved consciousness and decreased mortality. It likely reflects good oral water (hypotonic fluid) intake in the setting of hypovolemia and it requires no therapy beyond rehydration.

 

 

  1. S. S. Jamal Khan, F. R. Khan, M. Usman, and S. Zahid, “Malaria can lead to thrombocytopenia,” Rawal Medical Journal, vol. 33, no. 2, pp. 183–185, 2008.

  2. T. S. Faseela, R. A. Roche, K. B. Anita, C. S. Malli, and Y. Rai, “Diagnostic value of platelet count in malaria,” Journal of Clinical and Diagnostic Research, vol. 5, no. 3, pp. 464–466, 2011.

  3. A. Rasheed, S. Saeed, and S. A. Khan, “Platelet count in malaria,” Pakistan Journal of Phytopathology, vol. 19, no. 3, pp. 86–88, 2008.

  4. Thrombocytopenia as an Indicator of Malaria in Adult Population (hindawi.com)

 

Special thanks to Dr Woon Nga Tan for presenting this case