[Chemotherapy for human immunodeficiency virus infection. Current status and perspectives]

The role of drugs inhibiting viral replication in patients infected with HIV has been confirmed. Until now only dideoxynucleosides, which are reverse transcriptase inhibitors, have demonstrated antiviral activity in humans. A number of compounds acting on other steps of the viral cycle are currently being evaluated and clinical trials are being performed. Some investigators are attempting to inhibit the binding of viral particles to target cells and their penetration into these by acting on the interaction between HIV ant the CD4 molecule. Another approach consists in the characterization of enzymatic activities which are specific of HIV, other than reverse transcriptase, such as ribonuclease H, integrase or protease, in order to prepare specific inhibitors. Attempts are made to inhibit retroviral gene expression and production of viral particles in infected cells. The development of new nucleoside analogues and drugs with mechanisms of action and toxicities different from those of zidovudine should allow in the near future combination chemotherapy of HIV infection.

Cryptosporidium parvum sporozoite staining by propidium iodide

Modified Ziehl-Neelsen (ZN) acid-fast stain is the usual method for detection of Cryptosporidium oocysts in feces. Propidium iodide permitted us to stain free or intra-oocyst sporozoites. With the ZN method only 3-5% of the oocysts purified from three human and one experimentally infected lamb dichromate-preserved feces were stained by carbol fuchsin. These fuchsin-stained oocysts were free of intact sporozoites as identified by propidium iodide staining. Treatment with 10% formalin or 0.5% sodium hypochlorite increased the percentage of acid-fast stained oocysts and thus the sensitivity of acid-fast staining. Treatment with sodium hypochlorite induced intra-oocyst sporozoite alterations as demonstrated by flow cytometric analysis of the oocysts' DNA content. Propidium iodide staining of fixed oocysts is a simple and rapid method to visualize sporozoites and to assess oocyst preservation after different treatments.

Severe falciparum malaria (21 cases)

The incidence of severe falciparum malaria is increasing in the developed countries and mortality remains high despite progress in intensive care management and schizonticide treatment. Many authors emphasize the importance of exchange transfusion (EXT) in the most severe cases. We studied 21 cases (34 +/- 12 years, 6 females; SAPS: 8.4 +/- 3.7) of severe malaria (according to WHO criteria) consecutively admitted to ICU between 1985 and 1990: 3 patients underwent EXT. Twenty were febrile above 39 degrees C, 10 had cerebral malaria, 14 hepatic impairment, 8 acute renal failure, 5 pulmonary oedema. Nine patients required mechanical ventilation, 1 haemodialysis, 1 intracranial pressure monitoring. Mean parasitemia was 13%, 16 patients had thrombocytopenia less than 50 x 10(9)/l, 3 anemia less than 7 g/dl and 3 leucopenia less than 2.8 x 10(9)/l. Nineteen received quinine i.v., 1 mefloquine, 1 chloroquine. Sixteen patients received blood products transfusion, 3 were treated by EXT in addition. Twenty were cured and discharged from hospital without sequelae (mean stay: 14 days); 4 had nosocomial infection, 1 a splenic infarction. One patient (17-years-old; SAPS: 17; parasitemia: 7.8%) died 12 h after admission from non-cardiogenic pulmonary oedema with multi-organ failure. The literature and this study lead us to propose EXT in patients with unfavourable evolution after conventional treatment rather than in all the patients with a parasitemia above 10% at admission. A randomized study to compare conventional treatment in ICU with or without EXT is necessary.

Acute silicosis due to inhalation of a domestic product

A 20-yr-old woman with no history of pulmonary disease presented with acute dyspnea and fever. After various investigations and treatments the symptoms persisted and a lung biopsy was performed. Pathologic analysis disclosed the presence of silicotic crystals within lung tissue and mediastinal lymph nodes. The patient admitted having repeatedly inhaled a domestic scouring powder rich in silica during the preceding 6 months. This is the first report of acute pulmonary silicosis developing after exposure to a common household product.

[Treatment of salmonellosis and shigellosis with the new quinolones]

Sixty patients with enterocolitis (36 men, 24 females), mean age thirty seven (12 to 84) have been treated with new quinolones. Two groups have been constituted. First group included patients without bacteremia despite enterocolitis. Among them, 9 patients suffered from shigellosis (8 S. flexneri, 1 S. sonnei). Twenty-two patients had a minor salmonellosis (13 S. typhimurium, 4 S. enteritidis, 1 S. blockley, 1 S. Virchow, 1 S. london, 1 S. baildon, 1 S. C2 group). Patients in the second group underwent a septicemic salmonellosis (18 S. typhi, 3 S. paratyphi, 8 other Salmonella serotypes). All patients but one received an oral treatment. Forty-seven patients received 400 mg/day ofloxacin, 8 patients 1.500 mg/day ciprofloxacin, 5 patients 800 mg/day pefloxacin. Treatment lasted an average of 10 days (5 to 31 days). Apyrexia was observed within an average of 3 days (1 to 8 days). Blood culture have always been sterile after a two days treatment duration. No more shigella or salmonella was found in feces, five days after beginning of treatment. No relapse has been observed within a 30 days mean background (1 to 180 days). Not any intolerance needed to stop treatment. Patients have been hospitalized on an average of 11 days. Therefore, new quinolones will represent an effective, well tolerated treatment for salmonellosis or shigellosis.