*4.2.1.3. Leucopaenia*

Leucopaenia is the reduction in total white blood cell (WBC) count. In adults, normal WBC count is between 4.5 to 11.0 x 109 /L. Leucopaenia is frequently seen in HIV patients and predominantly due to lymphopenia, decrease in the number of lymphocyte count, mainly CD4+ lymphocytes. Leucopaenia generally correlates with the disease progression in HIV patients [62]. Reduction in absolute number of CD4+ T-cells occurs as one of the earliest immunologic abnormalities of HIV infection and is one of the important prognostic indicators of risk of developing opportunistic infections.

Production of granulocytes and monocytes is also reduced, but less well recognized feature as compared to lymphopaenia. Occurance of neutropaenia is hinged on several other factors which are commonly seen in patients with advanced HIV disease. It can also occur due to concurrent infections, immune mediated or therapy related factors. Another cause of neutro‐ paenia might be decreased bone marrow production of granulocytes due to inhibition of granulocyte progenitors. It has been postulated that a glycoprotein present in the marrow of infected patients might have an inhibitory effect [62]. Despite cellularity changes, morpholog‐ ical changes may occur in HIV patients. The changes are mainly due to dysplasia [38]. Peripheral blood smear will show some neutrophil changes such as detached nuclear frag‐ ments, abnormal nuclear fragmentation either hypofragmentation or hyperfragmentation, and abnormal nuclear granulation.

#### *4.2.1.4. Haematological changes in HIV infection with correlation to CD4 cell count*

In 2012, Parinithia and Kulkarni had done a study among 250 HIV patients to determine the haematological changes that occur in HIV patients as well as to evaluate its correlation with the CD4 cell count. They reported that among the HIV patients studied, anaemia, lymphopenia and thrombocytopenia was found in 210 (84%), 163 (65.2%) and 45 (18%) cases respectively [61]. Majority of the cases (70%) had CD4 cell counts below 200 cells/mm3 , 54 cases (21.6%) had CD4 cell counts between 200 to 499 cells/mm3 and in 21 cases (8.4%), the CD4 count is more than 500 cells/mm3 . In patients with CD4 cell counts less than 200 cells/mm3 , anaemia, leucopenia, lymphopenia and thrombocytopenia was observed in 91.4% 26.8%, 80% and 21.7% cases respectively [61]. This study revealed that there was a significant increase in the number of cases of anaemia and lymphopenia with decreasing CD4 cell counts. Thrombocytopenia was also seen but did not show significant increase with disease progression.
