Gram negative bacteria and contact lens induced acute red eye.

Two patients using hydrogel contact lenses on a daily wear schedule slept overnight with the lenses and woke up with a Contact Lens Induced Acute Red Eye (CLARE). The contact lenses recovered aseptically at the time of the event grew significant colonies of Pseudomonas aeruginosa and Aeromonas hydrophila in patient A and Pseudomonas aeruginosa and Serratia liquefaciens from patient B. Similar organisms from the contact lenses were recovered from the lens case and lens care solutions of patient B. In both the patients the condition resolved on discontinuation of lens wear. Patient compliance as a requirement for successful contact lens wear is highlighted with the illustration of these cases.

Assessment of suitability & ease of performance of seven commercial assay systems for the detection of antibodies to HIV-1.

In this study, we have evaluated the suitability and ease of performance of seven HIV assays namely: Vironostika anti-HIV Uni-Form; Vironostika HIV MIXT; Elavia MIXT; Genelavia MIXT; Serodia-HIV; Immunocomb Bi-spot; and Test pack HIV-1 and 2 Abbott, for use in Indian laboratories. A panel of 41 blind coded Western blot confirmed sera were used for this purpose. Rapid assays like Immunocomb Bi-Spot, Serodia HIV and Test pack HIV-1/HIV-2 Abbott were found to be more suitable and easy to perform as compared to the ELISAs. Sensitivity of all the assays was excellent (100%). Specificity of Serodia HIV, Immunocomb Bi-spot, Test pack HIV-1 and 2 Abbott and Elavia MIXT were excellent (100%), while that of Vironostika MIXT and Vironostika anti-HIV Uni-Form was poor. Positive predictive value of the assays ranged from 64.5 to 100 per cent. Negative predictive value of six of the assays was 100 per cent and that of Vironostika anti-HIV Uni-Form was very poor.

Pathological lesions in HIV positive patients.

Pathomorphological features of 10 HIV positive individuals studied at autopsy and biopsy are described. Nine patients had evidence of neuro-AIDS and eight of them succumbed to various opportunistic infections. One surviving patient underwent a diagnostic lymph node biopsy which revealed tuberculous lymphadenopathy. Cryptococcal meningitis was the commonest CNS opportunistic infection, seen in five cases, with disseminated systemic cryptococcosis in two. The other opportunistic infections included toxoplasma encephalitis in two, with acanthamoeba infection in one patient. Pulmonary tuberculosis was noted in three patients while other bacterial infections such as meningococcal meningitis, pseudomonas septicaemia were observed in three and pneumocystis carinii pneumonia in one. One seropositive individual was clinically asymptomatic but succumbed to a road traffic accident. The brain in this case showed features of HIV associated early leucoencephalopathy. Bacterial infections caused by organisms other than Mycobacterium tuberculosis associated with AIDS are often underdiagnosed and should be considered, especially in developing countries. In cases of cryptococcal and tuberculous meningitis or multiple parasitic infections, the patients should be screened for associated HIV infection.

The role of immunological & virological techniques in the diagnosis of herpes simplex encephalitis.

The efficacy of immunological and virological methods in the diagnosis of herpes simplex encephalitis (HSE) was studied in 22 patients diagnosed as HSE by clinical, radiological EEG parameters. CSF cell counts were elevated in 14 of 18 patients with a lymphocytic predominance in 13. Virus specific IgG antibody detection by ELISA in paired CSF samples was possible in 8 of 17 patients. HSV antigen could be detected by immunohistochemical methods in the cells of the CSF and/or brain tissue in 7 of 9 patients. In four of them antemortem diagnosis was possible facilitating prompt specific antiviral therapy. Virus isolation was possible in 2 of 8 patients, one from brain biopsy tissue and the other from brain tissue obtained at autopsy. Using all the three methods, the diagnosis of HSE could be confirmed in 14 of 22 (63.6%) patients.