Phylogenetic relationships between Puerto Rico and continental USA HIV-1 pol sequences: a shared HIV-1 infection.

In order to investigate the existing notion that the human immunodeficiency virus type 1 (HIV-1) infection in Puerto Rico (PR) was imported from the continental United States of America (USA) we sequenced and analyzed 900 bases of the HIV-1 pol sequence from individuals in PR for comparison with pol sequences from the USA mainland. The sequences were derived by direct sequencing of reverse transcription-polymerase chain reaction products generated from plasma virus. The products were sequenced in both directions and the complementary strands were compared prior to analysis. These processed sequences and GenBank sequences from the continental USA were subjected to phylogenetic analyses. The PR and USA sequences did not form independent clusters, indicating a shared HIV-1 infection. This may be due to the continuous human traffic or, less likely, may indicate a similar evolution of a common source virus. Analysis of drug resistance mutations, fairly similar in frequency in the PR and USA sequences analyzed here, supports human traffic as a rationale for the common infection. This work indicates that an efficacious vaccine developed for use in the USA mainland will also be effective in prevention in PR and perhaps the other countries of the Caribbean region.

Penicillin V and rifampin for the treatment of group A streptococcal pharyngitis: a randomized trial of 10 days penicillin vs 10 days penicillin with rifampin during the final 4 days of therapy.

To improve the bacteriologic and clinical cure rates of streptococcal pharyngitis, 79 children were randomly assigned to receive penicillin V alone for 10 days (39 patients) or penicillin for the same duration and rifampin during the last 4 days of penicillin therapy (40 patients). Eleven patients given penicillin had evidence of bacteriologic failure (including eight with relapse of clinical illness) on repeat cultures done 4 to 7 days after treatment, whereas there were no failures in children given combination therapy (P = 0.0015). All eight symptomatic children improved with penicillin-rifampin therapy and subsequent cultures were negative, whereas three asymptomatic children continued to harbor group A streptococci even after combination therapy. Antibody response by antistreptolysin O or antideoxyribonuclease B assay was seen in 50.6% of patients; the antibody responses in both groups were comparable. These results show that addition of rifampin to the penicillin regimen improves the clinical and bacteriologic cure rates in children with streptococcal pharyngitis.

Comparison of pentamidine isethionate and trimethoprim-sulfamethoxazole in the treatment of Pneumocystis carinii pneumonia.

Fifty patients with P. carinii pneumonitis were randomized to receive either pentamidine isethionate or trimethoprim-sulfamethoxazole therapy. Those not responding favorably to the first drug after three or more days of therapy were changed to the alternate drug. Of the 26 patients initially treated with TMP-SMZ, 20 recovered (0.77)-17 after TMP-SMZ alone and three of nine who were crossed over to pentamidine. Of the 24 patients initially treated with pentamidine, 18 recovered (0.75)-14 of 15 who received only pentamidine and four of nine who were crossed over to TMP-SMZ. Abnormal values for blood urea nitrogen, creatinine, or glucose; inflammation at injection sites; or combination of these effects occurred in 14 of the 15 patients treated with pentamidine alone. Only one of the 17 patients treated with TMP-SMZ alone developed any of these abnormalities. This study shows that TMP-SMZ is as effective as pentamidine in the treatment of PCP, and that it offers the advantages of minimal adverse effects, oral administration, and ready availability.