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according to estimates from the unaids global report 2010 , at the end of the year 2009 the prevalence of hiv worldwide was around 30.8 million in adults and 2.5 million in children .
aids killed 2.1 million people in the course of that year , including 3,30,000 children , and 76% of those deaths occurred in sub - saharan africa . unfortunately , these are the areas where tuberculosis ( tb ) has been flourishing unhindered , forming a deadly combination . the advent of hiv / aids has led to a dramatic increase in the number of tb cases worldwide . the etiology of kaposi 's sarcoma is multifactorial and a combination of immunosuppression combined with a hereditary predisposition to the disease is responsible for the major increase in its incidence in renal transplant recipients . we present a case of a 51-year - old tanzanian male hypertensive renal transplant recipient , who came to our attention when he presented with kaposi sarcoma , and later with hiv infection 6 years after transplantation along with allograft tb and bk viremia .
a 51-year - old male from tanzania , a hypertensive , on maintenance hemodialysis since june 2005 , underwent a live related renal transplantation on 13/09/2005 .
his serology for hiv 1 and 2 , hepatitis b , hepatitis c was negative .
he had a history of blood transfusion ( 6 units ) in june 2005 in his native country .
he was inducted with a single dose of basiliximab on the day of transplantation and his immunosuppressants were prednisolone 15 mg , mycophenolate mofetil ( mmf)500 mg b.d , cyclosporin 175/150 microemulsion on discharge while returning to his country .
on discharge ( 6/10/2005 ) his blood urea was 31 mg / dl and serum creatinine was 1.1 mg / dl .
he came back for a review 1 year later when his investigations showed urea 36 mg / dl , creatinine 1.2 mg / dl .
three months later , he presented with a rapidly progressive ulcerative lesion on his right thigh associated with swelling of the right lower limb .
the ulceroproliferative lesion was 20  15 cm with skin discoloration and bilateral palpable inguinal lymph nodes .
investigations showed urea 53 mg / dl , creatinine 1.4 mg / dl , sodium 133.4 meq / l , potassium 4.09 meq / l , chloride 107 meq / l , and bicarbonate 23.2 meq / l .
wedge biopsy of the skin lesion showed pseudoepitheliomatous hyperplasia and inguinal lymph node biopsy suggesting features consistent with kaposi sarcoma [ figure 1 ] .
repeated testing of hiv was negative and staining for acid - fast bacilli was negative epstein - barr virus igg 22.6 and igm 8.5 . he was started on chemotherapy ( liposomal doxorubicin ) .
mmf was stopped , and cyclosporin and prednisolone were tapered with the plan of stopping in 2 - 3 weeks .
on discharge , his investigations were urea 44 mg / dl , creatinine 2.3 mg / dl , sodium 124.6 meq / l , potassium 5.03 meq / l , chloride 96 meq / l , bicarbonate 18.6 meq / l , hb 8.4 gm / dl , and twbc 7500 cells / mm .
he received three doses of chemotherapy . on follow - up , his kaposi sarcoma lesion had regressed .
his follow - up on 8/12/2007 was uneventful with blood urea 42 mg / dl , creatinine 1.5 mg/ dl , and he was continued on the same line of treatment .
his investigations were blood urea 91 mg / dl , creatinine 3.1 mg / dl , sodium 133 meq / l , potassium 3.7 meq / l , chloride 98 meq / l , bicarbonate 25.8 meq / l , c alcium 9.2 mg / dl , phosphorus 3.4 mg / dl .
he tested positive for hiv with a viral load of 564407 iu / ml , cd4 count was 241 cells / ml and cd8 was 846 cells / ml .
renal biopsy suggested features of chronic allograft nephropathy ( can ) [ figure 2a ] with ill- defined granulomas suggestive of tb [ figure 2b ] .
he was started on antituberculous therapy ( att ) ( isoniazid 150 mg once a day , pyrazinamide 750 mg twice a day , levofloxacin 500 mg twice a day , pyrodoxine 40 mg once a day ) .
antiretroviral drugs ( zidovudine 300 mg twice a day , lamivudine 150 mg twice a day , efavirenz 600 mg twice a day ) were initiated after discussion with i d consultant .
his sirolimus dose was reduced to 3 mg once daily with a through level of 4.56 ng / dl .
( b ) a fragment of necrotic tissue is seen along with an ill - defined epithelioid granulomatous inflammation
this case report illustrates a post - renal transplant patient with newly diagnosed hiv infection with a high viral load .
he was switched over to sirolimus monotherapy , which inhibits the progression of dermal kaposi 's sarcoma in kidney - transplant recipients while providing effective immunosuppression .
subsequently , he tested positive for hiv and renal biopsy and nuclear amplification test showed evidence of tb and he was started on antiretroviral therapy and antituberculous drugs .
the sensitivity of the nuclear amplification test is 63 - 95% and the specificity is 96% . as the method used
is an rna polymerase rpob and pcr assay based on dna coding for 16s rrna , the false positive rate is less than 10% .
his sirolimus dose was lowered , as lowering the dose of sirolimus with antiretroviral therapy ( art ) has been shown to improve kidney function , showing that combination of immunosuppression with art may be nephrotoxic . while efavirenz is recommended at 600 mg once daily for adults weighing 88 pounds , as att therapy was also initiated , we increased the dosage of efavirenz . despite discontinuing calcineurin inhibitor ( cni ) in 2006 , while continuing rapamycin as a monotherapy , he had progression of can . in a study by kumar et al .
, it was shown that hiv patients maintained on art are capable of mounting an immune response , with a rejection rate of 25% .
rifampicin induces cytochrome p450 , which is responsible for metabolizing cyclosporine , sirolimus , and prednisolone .
this unpredictable interaction has led to acute rejections in 30% and graft loss is 20% , and hence rifampicin should be avoided in kidney transplantation .
the monitoring of patients on combined immunosuppression , att , and art is challenging due to major drug interactions and requires meticulous surveillance .
managing the pharmacokinetics , the complicated drug interaction profile , and combined toxicity of immunosuppressants , att , and art is a complex task .
there are no data regarding long - term outcomes of combining immunosuppressant with art and att .
long - term studies of patient and graft outcomes and the effect of prolonged immunosuppression on hiv therapy are required . in large parts of the world
the duration of att in post - transplant immunosuppressed patients with hiv infection should be 18 months . the defervescence and relief of hematuria suggested response to att .
show infection rates of over 300/100000 , often commonly in association with underlying hiv infection .
a majority of people with hiv infection are asymptomatic for substantial and variable length of time . when cd4 < 100/mm , disseminated infections are common with low virulence organisms .
our patient had cd4 240 mm ; hence , there was functioning immune response to normal organisms . as hiv infection progresses , the viral load rises and cd4 count falls .
most patients seroconvert within 4 to 10 weeks and 95% seroconvert within 6 months.[911 ] the median time from exposure to positive serology in one study was 63 days .
hence , it is very unlikely that he was in the pre - serology conversion stage at the time of diagnosis of kaposi sarcoma .
0.2% of all kaposi 's sarcoma is the classical non - hiv form and hence , non - hiv kaposi sarcoma ( ks ) is extremely rare .
the bk viremia is another complex issue in this patient who was on monotherapy with sirolimus .
reduction of sirolimus dosage and follow - up for bk viremia is an essential step in the management of this patient . in conclusion , we present a male patient with can , late onset hiv infection , previous treated kaposi sarcoma , bk viremia , and allograft tb .
in this report , we discuss a case of a 51-year - old african renal transplant who presented with metastatic kaposi sarcoma 1 year after transplant . 
 the kaposi sarcoma was treated with a switch of immunosuppressants and chemotherapy . 
 six years after transplant , he presented with chronic allograft nephropathy , allograft tuberculosis , bk viremia , and was diagnosed to have contracted hiv infection .