To investigate the clinical value of lactate dehydrogenase in diagnosis of opportunistic infections in patients with HIV infection.

Total of 708 patients with HIV infection admitted for the first time during January 2010 to December 2015 in Shenzhen the Third People’s Hospital were analyzed, retrospectively. The clinical characteristics and levels of serum lactate dehydrogenase (LDH) were collected after admission. According to the reference value of serum LDH (LDH > 250 U/L and≤250 U/L), the patients were divided into two groups: elevated LDH group (245 cases) and normal LDH group (463 cases).

Among the 708 patients with AIDS who were admitted to hospital for the first time, there were 132 female cases and 576 male cases. In LDH elevated group, there were 182 cases with opportunistic infection (Waldχ²= 29.675,P< 0.001), and 162 cases with pulmonary infection (Waldχ²= 69.328,P< 0.001). The results of Logitic regression single factor analysis showed that lower CD4⁺ T counts (Waldχ²= 60.646,P< 0.001), higher HIV loads (Waldχ²= 25.305,P< 0.001), fungal infections (Waldχ²= 67.264,P< 0.001) and pneumocystis pneumonia (Waldχ² = 101.892,P< 0.001) were more likely to lead to elevated LDH in patients with AIDS, with significant differences. In patients withMycobacteriuminfection, the level of serum lactate dehydrogenase was not easy to increase, without significant difference (Waldχ²= 0.137,P= 0.711). The results of Logitic regression multi-factor analysis showed that HIV RNA viral load>10⁷copies/ml (Waldχ² = 5.175,P= 0.023), pulmonary infection (Waldχ² = 5.096,P= 0.024), blood stream infections (Waldχ²= 9.443,P= 0.002), pneumocystis pneumonia (Waldχ²= 57.216,P < 0.001), fungal infections (Waldχ²= 6.064,P= 0.014) were associated with LDH elevation, with significant differences.

The increase of LDH in patients with AIDS indicated that the infection site tends to be pulmonary infection and blood flow infection, and the infection pathogen tends to PCP and fungal infection, which had certain early clinical diagnostic value.