Spectrum of opportunistic infections among HIV seropositive patients in Delhi region-a study by Delhi state AIDS control society

Background: HIV infection leads to AIDS and opportunistic infections are major cause of morbidity and mortality of such patients which considerably affect the health and quality of life of people infected with HIV. Hence the present study was carried out to find out the most common opportunistic pathogen and different opportunistic pathogens infecting HIV seropositive patients in Delhi region, India. Methods: This observational study was conducted in period from April’2013 to March’2014. During the period, total of 22,578 HIV seropositive patients were under active care of 9 ART centers of Delhi State AIDS Control Society (DSACS) till March’2014. Patients were grouped according to age as children (≤15 years of age) and adults (>15years of age) and evaluated for 13 major opportunistic infections. Results: During the period, 2725 cases were diagnosed and treated for OIs amongst HIV seropositive patients assessed under active care of ART centers. Tuberculosis accounts for maximum cases with 28.07%. Second most common OI reported was Candidiasis with 18.79% cases. Other OI reported were Bacterial Infections (Respiratory), Diarrhea, Bacterial Infections (skin) and Herpes Zoster with distibution of 15.5%, 14.53%, 6.64% and 3.78% respectively. Conclusion: This study is the first study ever on cumulative reported data on OI’s among HIV/AIDS patients on active care from DSACS (Delhi) showing the real-time distribution from Northern India. This will serve as a matrix for future evaluation.


Introduction
Globally, there were approximately 35.3 [32. 2-38.8] million people living with HIV in 2012. The adult HIV prevalence at national level is 0.27% as estimated in 2011 and has recently been estimated that 2.5 million individuals are living with HIV infection in India [1]. HIV infection leads to AIDS and major cause of morbidity and mortality of such patients are opportunistic infections and considerably affect the health and quality of life of people infected with HIV [2].
The depletion of T-lymphocytes which result from the proliferation of HIV causes the immune system to become severely compromised and the usually benign infectious agents become pathogenic. A number of microorganisms can be responsible for such opportunistic infections (OI's) in HIV-infected persons who have progressed to AIDS [3,4]. Global evidence suggests that the overall incidence of opportunistic diseases increases with the degree of immunosuppression resulting from HIV disease progression [5,6].
More than 9.7 million people living with HIV in low and middle income countries were receiving ART at the end of 2012. Of this, about 640000 were children. The Antiretroviral Therapy (ART) started in the mid 1990s was instrumental in reducing the mortality related to HIV infection. ART not only reduces the incidence of OIs but also improves survival rate of PLHIVs. In India, Treatment of Opportunistic Infections (OI) is one of the main goal of comprehensive management to People living with HIV/AIDS (PLHIV) served through Care, Support and Treatment (CST) component of the, National AIDS Control

Materials and methods
This observational study was conducted in period from April' 2013 to March' 2014. During the period, total of 22,578 HIV seropositive patients were under active care of 9 ART centers of Delhi State AIDS Control Society (DSACS) till March'2014. Patients were grouped according to age as Children (≤15 years of age) and Adults (>15years of age). These patients included PLHIVs put on Antiretroviral therapy and PLHIVs not started on Antiretroviral therapy. They reportedly visited ART centers at least twice in a year or more frequently from April' 2013 to March'2014 and were assessed and treated for Opportunistic Infections. The clinical assessment and examination of the cases was done by Senior Medical Officer/Medical Officer of the respective ART center. Laboratory investigations were prescribed on case to case basis. With CD4 cell count test advised every six months.
These patients presented of various signs and symptoms like weight loss, loss of appetite, chronic diarrhoea, dysphagia, chronic cough etc. However some patients came for voluntary testing as well. Patients were evaluated for 13 major opportunistic infections. A specific opportunistic infection was diagnosed on the basis of standard clinical definition and by laboratory procedures [12,13]. Tuberculosis is diagnosed and treated as per Revised National Tuberculosis Control Programme (RNTCP) guidelines.

Results
In the capital of India, with total population of more than Two billion, the prevalence of HIV is 0.30%. The total HIV seropositive people registered at ART centers of Delhi till March 2014 were reportedly 42,590, and total number of HIV seropositive people ever started on ART was 23128. The cumulative number of people living with HIV in Active Care at the end of March 2014 was 22578 (16038 PLHIVs on antiretroviral treatment (ART) and 6540 PLHIVs registered in the programme but not initiated on ART). Among this group, 59.25% were males, 32.39% were females, 1.40% was transgender/transsexual and 6.94% were children ≤15 years of age. During the period, 2725 cases were diagnosed and treated for OIs amongst HIV seropositive patients assessed under active care of ART centers. The distribution pattern of different opportunistic infections cases among PLHIVs were recorded and shown in Table 2. Tuberculosis accounts for maximum cases with 28.07%. Second most common OI reported was Candidiasis with 18.79% cases. Other OI reported were Bacterial Infections (Respiratory), Diarrhea, Bacterial Infections (skin) and Herpes Zoster with distribution of 15.5%, 14.53%, 6.64% and 3.78% respectively. The distribution of different OI's in percentage and total number is shown in Figure 1.
Other infections like Pneumocystic Carinii Pneumonia (PCP), CMV retinitis, Cryptococcal Meningitis, Mycobacterium Avium Complex (MAC) were of low incidence; respectively 1.14%, 0.55%, 0.88% and 0.48%. Out of all, 6.57% were categorized as "others", which included cases showing sign & symptoms of psychological disorder, lymphadenopathy or other infections not listed in the categories as mentioned in Table 2.

Discussion
Although the Human Immunodeficiency Viruses are the initial causative agents in AIDS, most of the morbidity and mortality seen in the case of AIDS patient results from the opportunistic infections which take advantage of the lowered cellular and humoral defence mechanisms of the patient.  in this population worldwide. It kills nearly a quarter of a million people living with HIV every year [14]. Mycobacterium tuberculosis was the commonest isolate reported responsible for Tuberculosis in few studies from India [15,16]. Similar finding is reported in our study, with TB as the most prevalent OI with 28.07% prevalence (32.8% in adults and 4.2% in pediatric group). Higher incidence of TB (71.1%) was also reported in New Delhi by Sharma et al. [17]. In the current study, out of 765 total reported cases of TB, 51.2% (392 cases) were Extra pulmonary in nature while 48.8% (373 cases) were had Pulmonary TB infection. Kumarasamy et al., from southern India in a retrospective analysis of 594 HIV-positive patients however reported higher incidence of Pulmonary Tuberculosis (PTB) (49.3%) in respect to Extrapulmonary Tuberculosis (EPTB) (11%) [18]. This diverse finding may further be researched for susceptibility of PLHIVs towards acquiring pulmonary and extra pulmonary TB.
Gastrointestinal Infections are very recurrent in patients living with HIV/AIDS. It had been reported that in AIDS patients the occurrence of Diarrhea in developed countries is 30-60 per cent whereas it is 90% in developing countries. C. parvum (54%) was the predominant pathogen among the opportunistic parasites. Several studies from India and other parts of the world also have reported the same [19][20][21]. In our study, Diarrhoea presented as third commonest OI with 14.53% cases. Even though Pneumocystic carinii pneumonia (PCP) is one of the most common opportunistic infections in AIDS patients, the rate of its recurrence among HIV/AIDS patients in tropical and developing countries is generally lower compared to that in industrialised nations [22]. Here also, the prevalence of PCP is demonstrated lower with 1.1% in adults and children.
A study from south India reported Oral Candidasis is in 59% of AIDS cases [23]. Since candidiasis is a frequent infection among PLHAs, it has been documented that it occurs in up to 70% of HIV infected cases [24]. Similar conclusions are obtained from current study that the second most common OI among PLHAs is candidiasis with 18.79% of prevalence. Saha et al., from Kolkata reported oral candidiasis (53.43%), chronic diarrhoea (47.05%), and TB (35.29%) as commonest opportunistic infection [25]. In another study, Patel from Ahmedabad revealed that candidiasis was the commonest isolate (32.67%), followed by TB (22.71%) [26]. Although TB is the most common OI in adult but Respiratory bacterial infection is the commonest OI reported among children in our study.

Conclusion
The first case of AIDS in India was reported in 1986. Now India is the country with the second largest population of HIV infected individuals. The emergence and pandemic spread of AIDS constitute the greatest challenge to public health in modern time. With the changing scenario of AIDS epidemic, a host of opportunistic infections add to the present endemic state of some already existing infections like tuberculosis.