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lymphatic filariasis is common in tropical countries and is endemic in india with most infections caused by wuchereria bancrofti .
the microfilaria are not just confined to the lymphatic system , but also associated with other organs , subcutaneous tissues , and serous cavities like pleura and pericardium .
demonstration of microfilariae ( mf ) in the peripheral blood smear or in the tissues is the mainstay of diagnosis .
filariasis acutely presents with fever , adenolymphangitis , funiculitis , epididymitis , orchitis , or pericarditis .
lymphedema , hydrocele , elephantiasis and chyluria , and pleural or pericardial effusion are features of chronic infection .
our case was a rare as recurrent hemorrhagic pericardial effusion and tamponade , which was first treated with diethyl carbamazine and finally albendazole .
she complained of cough and breathlessness on exertion and low grade fever since 3 weeks and generalized weakness since 1 week . on examination , she was severely dyspneic and had pulsus paradoxus . echocardiogram showed massive pericardial effusion with cardiac tamponade [ figure 1 ] .
apical four - chamber view showing large pericardial effusion with right atrial collapse ( left ) and parasternal short axis view showing large pericardial effusion with right ventricular outflow tract ( rvot ) diastolic collapse ( right ) pericardiocentesis was done and 1,300 ml of hemorrhagic fluid was collected .
results of complete blood picture were : total count - 6,800/mm , polymorphs - 67% , lymphocytes - 23% , eosinophils - 06% , monocytes - 04% , platelet count - 160,000/mm , hemoglobin - 11 g% , erythrocyte sedimentation rate ( esr ) - 40 1 h. , human immunodeficiency virus ( hiv)-nonreactive , and hepatitis b surface antigen ( hbsag)-negative .
complete urine examination , blood sugar , urea , creatinine , and electrolytes ; all were in normal range .
cytological analysis of fluid showed - 7,000 cells / mm , ( neutrophils - 35% , lymphocytes - 65% , plenty of red blood cells ( rbc ) ) , negative for malignant cells , sugar - 61 mg% , proteins - 6 g% , albumin - 2.5 g% , adenosine deaminase ( ada ) - 23 u / l , acid - fact bacilli ( afb ) - negative ; microscopy and routine cultures were negative for bacteria . while screening the smears , a few large , long , smooth - walled , refractile unstained worm - like structures were observed .
the organisms were identified as mf of w. bancrofti in the smears stained by leishman 's stain [ figure 2 ] .
cytology showed plenty of rbc , occasional pus cells , and microfilaria of w. bancrofti [ figure 3 ] .
the patient improved rapidly by next day and effusion was grossly reduced by the 2 day .
pericardial fluid cytology smear showing microfilaria of wuchereria bancrofti with occasional pus cells ( leishman stain , 1000 ) pericardial fluid cytology smear showing microfilaria of w. bancrofti with occasional pus cells ( leishman stain , 40 )
it is transmitted by the culex mosquito and is caused by two closely related nematodes , w. bancrofti and brugia malayi , which are responsible for 90 and 10% of the cases , respectively .
microfilaria have been confined not only to the lymphatic system but also associated with other organs , subcutaneous tissues , and serous cavities like pleura and pericardium .
pericardial effusion is a rare manifestation of filariasis , and recurrent effusion with tamponade is even more rare .
our case was of massive pericardial effusion established as filarial in origin on demonstration of mf in pericardial aspirate .
it might have lodged itself through blood stream subsequent to development of pericarditis . as mf are capable of penetrating the tissues of the vector , they can freely move in and out of small , delicate blood , and lymphatic capillaries and tissues of the vertebrate host .
peripheral blood smears may be negative for mf in cases of secondary manifestations of filariasis . in this case
patient developed effusion despite being treated with dec suggests that it may not be 100% effective in all cases as dec does not act on microfilaria residing in lymphatics , and they might have migrated to pericardial space causing recurrent effusion .
she was finally cured with alternate combination of ivermectin and albendazole , which makes it even more interesting .
although mf in unusual sites are considered incidental findings , on the basis of existing evidences we suggest that some of the cases of recurrent pericardial effusion , especially those from endemic areas , might be of filarial origin .
it is therefore emphasized that a thorough examination of the aspirated fluid for mf is warranted in all patients with unexplained pericardial effusion .
filariasis presenting with pericardial effusion with tamponade is rare . 
 we report a case of a 30-year - old female who was admitted with severe dyspnea and chest pain since 2 days . 
 echocardiogram showed massive pericardial effusion with tamponade . 
 pericardial fluid aspiration drained 1.2 l of hemorrhagic fluid . 
 cytology examination revealed microfilaria of wuchereria bancrofti . 
 she was treated with diethyl carbamazine and discharged . 
 six weeks later , she presented again with massive pericardial effusion with cardiac tamponade . 
 pericardiocentesis was done . 
 cytology examination revealed microfilaria of w. bancrofti . 
 this time she was treated with ivermectin and albendazole and cured . 
 hemorrhagic effusion resolved completely . though relatively uncommon , tropical diseases must always be considered in the etiological diagnosis of recurrent pericardial effusion .