A Study on the Clinical Presentation of HIV-TB Coinfection and Its correlation with CD4 Count

INTRODUCTION: The burden of TB and HIV /AIDS poses unprecedented challenges on the public health system in India. TB and HIV are overlapping epidemics. They are closely interlinked. Untreated HIV infection leads to progressive immuno deficiency and increased susceptibility to infections including TB. TB is the leading cause of HIV related morbidity and mortality. HIV is the most important factor fuelling the TB epidemic in populations with a high HIV prevalence in many countries especially in sub-Saharan Africa and increasingly in Asia and South America. Studies have shown that there is close association between HIV and TB. Evidence of this interaction included several observations repeatedly made by WHO, National governments and funding partners. These observations are • The areas that have been mostly affected by HIV epidemic also report the greatest increase in the incidence and prevalence of the TB. • The largest increase in TB cases has occurred among people aged 25-40 years. The very same age group mostly affected by HIV/AIDS. • TB is the most common opportunistic infection among AIDS patients(Between 60-75% of AIDS patients will develop TB). • HIV prevalence among TB patients is higher than in the general population. (It is estimated a prevalence of 5.2% of HIV in adult TB in India). AIM OF THE STUDY: 1. To study the clinical presentation of tuberculosis in HIV positive patients. 2. To study the correlation of CD4 count with the radiological findings of Pulmonary tuberculosis. MATERIALS AND METHODS: Place of Study : Department of Medicine, KMCH Type of Study : Cross sectional Study Collaborating Department : Chest Clinic, ART Clinic. Duration of Study : January 2006 to July 2007 Case Selection: INCLUSION CRITERIA: • Patients who have been diagnosed as HIV positive either by Rapid Test or ELISA and who have clinical and investigatory evidence of pulmonary TB or Extra pulmonary TB are enrolled in the study. These patients are picked up from ART Clinic. • Those patients who sought medical attention for any form of Tuberculosis at chest clinic OP, who are HIV negative, are chosen as controls. • Patients between the age group of 15 to 55 are enrolled in the study. EXCLUSION CRITERIA: • Patients below the age of 15 and above the age of 55 are excluded in the study. • HIV positive individuals who did not have clinical or investigatory evidence of any form of TB were excluded. • Patients who had other causes of immuno suppression such as Diabetes, Lymphoma, Leukemea, visceral malignancy, malnutrition, on immuno suppressive drugs were excluded. METHODOLOGY: All HIV positive patients were meticulously examined for the presence of Pulmonary and Extra pulmonary Tuberculosis. Their symptoms were analyzed in a detailed manner. Complete general examinations for presence of opportunistic infection and respiratory system and other system examination were done. All of them were subjected to the following investigations. Basic blood investigation, sputum smear for AFB, chest x-ray PA view, PPD reactivity by mantaoux test and CD4 count. Special investigations were done in patients with extra pulmonary TB like FNAC of lymphnode, biopsy, and CSF analysis. RESULTS: A total number of 60 patients of HIV +ve TB and 30 patients HIV -ve TB were enrolled in this study. All the data were fed into a computer and the results were collected using an epidemiology incorporated software. The following test statistics were used 1) two sample t test, 2) wilcoxon Rank Sum test/Mann -Whitney test, 3) Chi-square test, 4) Fisher -exact. CONCLUSION: 1. As TB is the most common opportunistic infection in all HIV positive individuals, hence all HIV patients should be screened for TB and all TB patients should be screened for HIV status. 2. Tuberculosis has multiple clinical presentations in patients with HIV infection. 3. Atypical chest x-ray findings are common in HIV-TB co infection. 4. The most common atypical presentations are mediastinal adenopathy, lower zone infiltration and miliary mottling. 5. Cavitation is rare in HIV-TB co infection. 6. When the CD4 count is more than 200, upper zone infiltration is more common. When the CD4 count less than 200 atypical xray findings are common. 7. Sputum smear negativity is more common,hence sputum culture is essential as a screening procedure . 8. Mantoux test often is false negative in HIV-TB co infection. 9. Lymphnodes, meninges and pleura are the common sites of extra pulmonary TB involvement. 10.Tuberculosis can occur at any level of depletions of CD4 count but when the CD4 count level is grossly low extra pulmonary TB is more common. Since TB-HIV fuel each other, early diagnosis and proper effective management are essential to reduce the morbidity and mortality