HIV-1 drug resistance mutations in children who failed non-nucleoside reverse transcriptase inhibitor-based antiretroviral therapy.

Non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens have recently been used in HIV-1 infected children in resource-limited settings. Treatment failure with this regimen has become more common. A second regimen needs to be prepared for the Thai national program. Genotypic resistance testing was conducted among HIV-1 infected children who experienced virological failure with antiretroviral therapy (ART) using NNRTI-based regimens. Patterns of resistance mutations were studied and options for a second regimen were determined. There were 21 patients with a median (IQR) age of 4.1 (1.9-7.7) years. Sixteen patients were males. The median CD4 cell count and HIV-1 RNA at the time of virological failure were 647 cells/mm3 and 5.3 log copies/ml, respectively. The prevalences of patients with > or =1 major mutation conferring resistance to NRTIs and NNRTIs were 52% and 43%, respectively. Thymidine analoque mutations, M184V/I, and Q151M were observed in 38%, 33%, and 5%. The patterns of resistance mutations suggest that 48% of patients need a protease inhibitor-based regimen for the second regimen and didanosine+lamivudine is the most required nucleoside reverse transcriptase inhibitor backbone.

A patient with penicillin-resistant viridans group streptococcal endocarditis and unusual reactions to vancomycin.

There is a paucity of data regarding the treatment of endocarditis caused by penicillin-resistant viridans group streptococci (PR-VGS). We report a 16-year-old girl who had native-valve endocarditis due to PR-VGS which was identified as Streptococcus mitis. She also had unusual reactions to vancomycin. Eighteen hours after initiation of 50 mg/kg/day vancomycin, she developed a maculopapular rash, then at 48 hours she developed an intermittent high fever and a progressive decrease in peripheral leukocytes and platelets. She developed hypotension on Day 8. Her serum C-reactive protein and procalcitonin levels were high. All reactions improved after vancomycin was discontinued and oral prednisolone was started. This unusual combination of reactions to vancomycin was likely caused by immune and nonimmune mechanisms. Her endocarditis was successfully treated with cefotaxime 200 mg/kg/ day for 4 weeks.

Utilization of restricted antibiotics in a university hospital in Thailand.

Antibiotic resistance, a major negative consequence of antibiotic overuse, is an important problem worldwide. Various means have been used to control antibiotic usage including the use of an antibiotic order form (AOF), restricted antibiotic formularies and provision of educational information. The present study was designed to evaluate the use of antimicrobials in a 1,000-bed university hospital. Antimicrobial agents, likely to be abused namely ceftazidime, cefepime, cefoperazone/sulbactam, imipenem/cilastatin, meropenem, ciprofloxacin, netilmicin, vancomycin, azithromycin and clarithromycin, were selected for evaluation. A simple AOF with educational information was used as a mean to follow up the treatment. The investigator collected data from the filled AOF and the patient's charts of the Department of Internal Medicine from June to November 2000; all relevant data were assessed. The appropriateness of antibiotic use, assessed according to the criteria specified in the AOF, showed that 74% of these antibiotics were prescribed appropriately; this may prove the effectiveness of the system used in the present study. However, 348 of the 430 prescriptions (80.9%) were prescribed empirically at the initial stage for treatment of nosocomial infections in patients with serious conditions like pneumonia, sepsis and febrile neutropenia. Drugs that were frequently used empirically were ceftazidime (37.9%), imipenem/cilastatin or meropenem (19.3%), and cefoperazone/sulbactam (12.1%) respectively. Ceftazidime and imipenem/cilastatin or meropenem were also frequently used inappropriately among 111 prescriptions that were classified as an inappropriate prescribing. The most common misuses were prescriptions of the drug that did not follow the specified indications (70 prescriptions), no dosage adjustment in patients with renal impairment (39 prescriptions), improper dose (12 prescriptions) and improper dosing interval (9 prescriptions). The results suggested overuse of certain antibiotics remain to be an unsolved problem. Better monitoring and strict controlled use of the problematic antibiotics, ie ceftazidime, imipenem/cilastatin or meropenem and vancomycin are essential to promote rational drug use as well as to reduce the frequency of drug resistance.

Prevalence of HIV-1 drug resistance in antiretroviral-naive pregnant Thai women.

HIV-1 drug resistance may limit the use of antiretrovirals when attempting to reduce the vertical transmission rate. Establishing the prevalence of the HIV-1 mutations associated with antiretroviral resistance in pregnant women will enable clinicians to maximize the chances of preventing vertical transmission. In order to determine the prevalence of HIV-1 resistant strains among antiretroviral-naive pregnant Thai women, the nucleotide sequences of the HIV-1 polymerase (pol) gene were evaluated. The plasma samples were collected from the women during the 34th week of pregnancy: numerous secondary mutations could be found in the reverse transcriptase (RT) and protease gene, while no primary mutations in the pol gene were found. The result also showed that by detecting the delta32bp deletion within the CCR 5 locus, it was evident that none of HIV-1 infected individuals had homozygous or heterozygous delta32bp deletions of the CCR5 gene; moreover, no CCR5 gene mutations were found in any individual.