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lower cd4 cell counts ( < 100/l ) , higher hiv-1 rna levels , clinical aids , opportunistic infections ( cytomegalovirus [ cmv ] or hhv-8 infection ) , drugs , and immune reconstitution after highly active antiretroviral therapy ( haart ) are the risk factors for thrombotic microangiopathy ( tma ) in hiv patients . we describe here a 52-year - old male patient who presented with tma and later found to have hiv positivity .
a 52-year - old - male was admitted to the emergency department with acute breathlessness , edema legs , and oliguria of 3 days duration .
investigation revealed urine analysis : 1 + proteinuria , no red blood cells ; 24 h urine protein : 1.2 g / day ; blood hemoglobin : 8 g / dl ; platelet count : 80,000 cells / mm ; peripheral smear : numerous fragmented red blood cells ; blood urea : 110 mg / dl ; serum creatinine : 7.5 mg / dl ; sodium : 130 meq / l ; potassium : 3.5 meq / l ; indirect bilirubin : 1.4 mg / dl ; serum lactate dehydrogenase ( ldh ) : 1200 u / l . prothrombin time , activated partial thromboplastin time and fibrin degradation products were all normal .
it was negative for hepatitis b and c. cd 4 count was 224 cells / mm .
he was started on haart ( lamivudine , nevirapine , and zidovudine ) and hemodialysis .
light microscopy showed double contour of the glomerular basement membrane and fibrin thrombi occluding the lumen of arterioles [ figure 1 ] .
tma involving kidney in an aids patient was first described by boccia et al . in 1984 .
the frequency of tma was found to be higher in hiv - infected patients than in normal population and greater in those with advanced disease .
the clinical spectrum varies from asymptomatic thrombocytopenia with mild renal failure to a serious illness with neurological deficit and dialysis requiring renal failure .
most of them have co - existing aids - defining illness such as pneumocystis carinii pneumonia , cmv retinitis , and cryptococcal meningitis .
the incidence of tma in hiv patients is decreasing after the introduction of haart . in a study conducted in milan ,
the incidence of tma was 1.4% in prehaart era whereas no cases were reported in the haart era .
it can be caused directly by viral invasion as evidenced by the expression of hiv-1 p24 antigen / chemokine receptors cxcr4 in endothelial cells or indirectly by the action of cytokines / hiv - associated proteins such as tat and gp 120 on endothelial cells .
complete deficiency of the vwf - cleaving protease adamts13 has been reported in hiv - associated tma due to the development of igg autoantibodies .
other factors include drugs ( valacyclovir , fluconazole , and clofazimine ) , malignancies , and direct vascular injury by infectious agents .
various inflammatory cytokines such as tumor necrosis factor- and interleukin-1 are found to be raised , and there is evidence of enhanced apoptosis of microvascular endothelial cells in these patients .
plasma exchange is the mainstay of treatment and renal involvement is generally last to improve .
it should be continued until the resolution of neurological symptoms and both a normal serum ldh and platelet count have been maintained for 3 days .
role of corticosteroids , splenectomy , and anti - platelet agents in patients with hiv - tma is unknown .
splenectomy and monoclonal antibodies should be reserved for those who are refractory to plasma exchange .
long - term prognosis of hiv - tma depends on the stage of hiv infection .
mortality of patients with symptomatic hiv infection is three times higher than mortality of patients with asymptomatic hiv infection .
patients with hiv - tma , who do not have aids , have favorable outcome when treated with plasmapheresis .
our patient presented with tma with severe renal failure as the initial manifestation of hiv .
he was treated with hemodialysis , supportive measures , and haart , and planned for plasmapheresis , but was not willing for further management .
thrombotic microangiopathy ( tma ) is characterized by microangiopathic hemolytic anemia , thrombocytopenia , microvascular thrombosis , and various organ dysfunctions . 
 tma usually occurs in a more advanced stage of hiv disease . 
 tma as an initial presenting feature is rare . 
 we here report a male patient who presented with oliguric renal failure . 
 investigations revealed anemia , thrombocytopenia , schistocytes in peripheral smear , and hiv - positive . 
 renal biopsy revealed tma . he was treated with hemodialysis and started on highly active antiretroviral therapy .