Liver Involvement in Falciparum Malaria A Histo-pathological Analysis

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1 ORIGINAL ARTICLE JIACM 2003; 4(1): 34-8 Liver Involvement in Falciparum Malaria A Histo-pathological Analysis Rajesh Baheti*, Purnima Laddha**, RS Gehlot*** Abstract The present study has been undertaken to evaluate the histopathological alteration in the liver due to P. falciparum. Does it help in diagnosis of PUO due to falciparum malaria when other methods of diagnosing falciparum malaria are inconclusive? 60 patients of slide positive falciparum malaria, age more than 18 years, were subjected to liver biopsy. The patients of known liver disease were excluded and histopathology slides were examined under light microscopy at Deptt. of Pathology, Dr. S.N. Medical College, Jodhpur. The specific histopathological changes in liver due to P. falciparum observed by us were RE cell proliferation - 90%, haemazoin pigmentation - 90%, congestion 80%, portal infiltration - 75%, sinusoidal infiltration and dilatations %, cholestasis - 40%, while minor changes in the form of nuclear vacuolation %, liver cell necrosis %, and vacuolated cytoplasm in 10%, of cases. Thus, liver biopsy may be helpful in diagnosis when other methods of diagnosing P. falciparum are inconclusive. Key words : Falciparum malaria, Liver. Introduction Nearly 2 million cases of malaria occur every year in India. As per WHO data, approximately 270 million cases suffer from malaria every year globally, with 1-3 million deaths annually, out of which 80% of the deaths are caused by P. falciparum 1. Falciparum malaria can mimic many diseases with its varied presentations and it must always be considered in the differential diagnosis of acute illnesses, like hepatorenal syndrome, fulminant hepatic failure, acute hepatitis, i.e., jaundice, encephalopathy, pulmonary oedema, anaemia, septicaemia, hypoglycaemia, acidosis, abdominal pain with diarrhoea, hepatosplenomegaly, renal failure, spontaneous bleeding and coagulopathy, hyper-pyrexia, and unarousable coma. Malarial involvement of liver is now a known entity with its specific histopathological changes and cases with altered liver function test and even fulminant hepatic failure and hepatic encephalopathy were reported 2,3,4,5. Liver biopsy may be a valuable tool to establish the diagnosis when other diagnostic methods are inconclusive and the histopathological changes due to malarial involvement of liver are specific 6,7,8 and may be an aid in the diagnosis of PUO. Material and methods Sixty cases of slide positive falciparum malaria, age more than 18 years, admitted to the medical units at Dr. S.N. Medical College, Jodhpur, during the period between January 1994 and July 1996 were included in the study. All patients were subjected to ultrasonography of liver. Patients of known liver disease like cirrhosis of liver, alcoholic liver disease, drug induced hepatitis, viral hepatitis, obstructive jaundice, chronic hepatitis, or any other liver disease were excluded. Patients with any other systemic illness were also not included in the study. 92 patients of P. falciparum were admitted during Jan. 94 to July 1996 of which 60 clinically stable slide positive P. falciparum cases were subjected to liver biopsy procedure after taking appropriate consent and obtaining bleeding parameters and approval from the ethical committee of the hospital. Patients were premedicated with injection diazepam and injection atropine. Area of liver dullness was marked and confirmed with ultrasonography of liver. The area was sterilised, the tissues upto the capsule of liver were infiltrated with Inj. xylocaine, 20ml syringe containing 5 ml normal saline with Menghini s needle was taken. The needle was inserted through the 9th or 10th intercostal space (usual area of liver dullness) upto the liver capsule, and about 1 ml of saline was injected in the capsule of * Department of Medicine, Dr. S.N. Medical College, Jodhpur (Rajasthan). ** Consultant, Kamla Nagar Hospital, Jodhpur (Rajasthan). *** Professor and Head, Deprtment of Medicine, Dr. S.N. Medical College, Jodhpur (Rajasthan).

2 liver to clear the needle of any tissue fragment. Thereafter, aspiration was begun exerting a constant negative pressure, with the patient holding the breath in expiration. Then the needle was quickly inserted into the liver substance and quickly withdrawn with the biopsy piece. This was transported in 10% neutral formalin to the deptt. of pathology, Dr. S.N. Medical College, Jodhpur, for histopathological analysis. congestion, portal infiltration, sinusoidal dilatation and infiltration. Discussion Liver involvement in malaria is common in patients of severe malaria and may manifest as jaundice i.e., raised serum bilirubin, hepatomegaly, elevated liver enzymes like aspartate and alanine transaminases. There may be a low Observations Histopathological features in liver due to P. falciparum. N=60 S. No. Histopathological features in liver due to PF malaria. No. of patients Percentage 1. Reticulo endothelial cell Proliferation, i.e., Kupffer cell hyperplasia % 2. Malarial pigmentation, i.e., haemazoin pigmentation % 3. Congestion % 4. Portal infiltration % 5. Sinusoidal infiltration and sinusoidal dilatation % 6. Cholestasis % 7. Nuclear vacoulation % 8. Liver cell necrosis % 9. Fatty change 9 15 % 10. Balloning of hepatocytes % 11. Vacoulated cytoplasm 6 10 % Note : We did not encounter any patient having parasitized red blood cell and malarial nodule. The specific histopathological changes in the liver due to P. falciparum infection noted by us in 60 patients, were : (a) Reticuloendothelial cell proliferation, i.e., Kupffer cell hyperplasia - 90%; (b) Malarial pigmentation, i.e., haemazoin pigmentation - 90%., (c) Congestion - 80%, portal infiltration - 75%, sinusoidal infiltration and dilatation %, and cholestasis in 40% of cases. (d) While minor changes in the form of nuclear vacuolation 23.3%, liver cell necrosis %, fatty change - 15%, ballooning of hepatocytes 13.3%, and vacuolated cytoplasm in 10% of cases were also observed. (e) The most consistent and commonest features were RE cell proliferation, haemozoin pigmentation, and falling serum albumin, and prothrombin time may be prolonged. Severe falciparum malaria may present as coma, jaundice, and renal failure and the severe disease must not be mistaken for fulminant hepatic failure as there is a better response to therapy in cases of malaria 2. 6 cases of severe jaundice and encephalopathy due to falciparum malarial hepatitis initially diagnosed as fulminant hepatic failure were reported, the liver function showed predominantly conjugated hyperbilirubinaemia with modest elevation of asparate, alanine transaminases, and alkaline phosphatase level, and it was concluded that liver biopsy is a valuable tool in establishing the diagnosis at all the stages of disease 3. Severe falciparum malaria may involve liver and kidneys Journal, Indian Academy of Clinical Medicine ❺ Vol. 4, No. 1 ❺ January-March

3 Fig. 1 : Photomicrograph showing swollen hepatocytes, RE cell prominence, sinusoidal dilatation, and haemazoin pigmentation (X 80). Fig. 2 : Photomicrograph showing prominence of Kupffer cell ladden with malarial pigment (x 200). and there may be altered liver function tests and azotaemia 4,5. The clinical and pathological manifestations of malaria are consequent upon the release of cellular products and debris from ruptured erythrocytes and their subsequent phagocytosis by the reticuloendothelial cells. P. falciparum is the only species of malarial parasite to be seen in human tissue sections and all observations regarding the histopathology of liver in relation to malaria have been made in relation to this species. During acute stage of an attack Kupffer cells are enlarged, and also increase in number, i.e., hypertrophy and hyperplasia. Thus, the liver is enlarged and may weigh upto 2.5 kg. Focal accumulation of histiocytes forming non-specific granulomatous lesions may be seen in the sinusoids 6,7. Liver is congested with a grey or black pigmentation as a result of accumulation of byproducts of the metabolism of haemoglobin by the parasite known as malarial pigment (haemozoin) which is a specific molecule consisting of iron and a protein moiety, i.e., an iron porphyrin complex that is phagocytised and processed by the macrophages, accumulation of these macrophages in the tissues gives the dark pigmentation to the organs. These macrophages accumulate in liver, spleen, and bone marrow. The pigment is seen as crystalline clump of dark green material that polarises under polarising light, i.e., (yellow, orange birefringerence). While haematoxylin-eosin (HE) stained tissue section reveals malarial pigment as coarse black granules or clumps within the Kupffer cells. Following survival of an acute attack, the pigment gradually migrates from parenchymal to portal areas. The presence of the pigment accentuates the lobular architecture 6,7. The most common histopathological feature in our study in the form of reticulo-endothelial cell proliferation, i.e., Kupffer cell hyperplasia (90%), malarial pigmentation, i.e., haemazoin pigmentation (80%), congestion (80%), portal infiltration (75%), sinusoidal infiltration and dilatation (71.6%), are observed as described earlier 6,7. 36 Journal, Indian Academy of Clinical Medicine ❺ Vol. 4, No. 1 ❺ January-March 2003

4 Microscopically, in acute malaria there is a pronounced hyperaemia, with dilatation of all capillaries and may have parasitised erythrocytes attached to the endothelial surface of the vessel and Kupffer cells may contain parasitised RBCs 8. However, we have not encountered any histopathological specimen having parasitised RBCs attached to endothelial surface of the vessel or in Kupffer cell 8. Further, we have not observed any evidence of fibrosis, cirrhosis, or liver cell mitosis in any of the histopathological specimens in concordance to others that fibrosis usually does not occur and malaria is not precirrhotic 8. Liver is congested and usually there is no parenchymal damage or cholestasis unless there has been shock and ischaemic necrosis. The cholestasis observed by us (40%) was matching with the other study 4 in which it was observed in 36% of cases. The fatty change (15%) and focal hepatocyte necrosis (18.3%) observed by us was similar to other study 9, usually attributable to poor nutritional status. The observation was in contrast to that observed by Fig. 4 : Photomicrograph showing swollen hepatocytes with foamy clear cytoplasm and dilated sinusoidal channel (x100). Mishra SK 5 and liver cell necrosis as a rare event was noticed by Joshi YK 3. References We have also observed nuclear vacuolation (23.3%), ballooning of hepatocytes (13.3%), and vacuolated cytoplasm (10%). But the malarial nodule was not observed by us. In one study the malarial nodule, i.e., granulomatous lesion with hepatocyte necrosis was the most consistent observation made in 50% of cases 10, while ballooning of hepatocytes (30%) and vacuolated cytoplasm were observed in (20%) of cases 10. Fig. 3 : Photomicrograph showing sinusoidal dilatation with lymphocytic cells with RE cell prominence (x 100). 1. Gilles HM. Management of severe and complicated Malaria. In: Warrell DA, Beales PF (eds.) Severe and complicated malaria, 2nd ed. Geneva : World Health Organization 1991; P5. 2. Anand AC, Ranji C, Narula AS et al. Malarial hepatitis; a heterogenous syndrome? National Med J India 1992; 5(2): Joshi YK, Tandon BN, Acharya SK. Acute hepatic failure due to P. falciparum liver injury. Liver 1986; 6: Chawala LS., Sidhu J., Sabharwal BD et al. Jaundice in P. falciparum. J Assoc phys India 1989; 37(6): Journal, Indian Academy of Clinical Medicine ❺ Vol. 4, No. 1 ❺ January-March

5 Fig. 5 : Photomicrograph showing periportal hypercellularity of inflammatory mononuclear cells (x100). Fig. 6 : Photomicrograph showing RE cell laden with malarial pigment (x 80). 5. Mishra SK, Mohanty S, Das BS. Hepatic changes in P. falciparum malaria. Indian Journal of Malaria. 1992; 29(3): Lichtenberg FV. Infectious diseases. Pathologic basis of disease 3rd ed. Publishers W.B. Saunders Company 1984; Kamal GI, Rodney SM. Liver. Anderson s Pathology Vol. 2, 10th Ed. Publishers Mosby 1996; Sherlock S. Diseases of liver and biliary systems - 3rd edition Oxford. Black well scientific publication 1975; 6: Srivastava A, Khanduri A, Lakhtakia S. Falciparum malaria with acute liver failure. Tropical Gastroenterology 1996; 17(3): Ramachandran S and Perera MV. Jaundice and hepatomegaly in primary malaria. Journal of Tropical Medicine and Hygiene 1976; 79: Journal, Indian Academy of Clinical Medicine ❺ Vol. 4, No. 1 ❺ January-March 2003