Combination treatment with zidovudine, didanosine, and nevirapine in infants with human immunodeficiency virus type 1 infection

BACKGROUND

In infants and children with maternally acquired human immunodeficiency virus type 1 (HIV-1) infection, treatment with a single antiretroviral agent has limited efficacy. We evaluated the safety and efficacy of a three-drug regimen in a small group of maternally infected infants.

METHODS

Zidovudine, didanosine, and nevirapine were administered in combination orally to eight infants 2 to 16 months of age. The efficacy of antiretroviral treatment was evaluated by serial measurements of plasma HIV-1 RNA, quantitative plasma cultures, and quantitative cultures of peripheral-blood mononuclear cells.

RESULTS

The three-drug regimen was well tolerated, without clinically important adverse events. Within four weeks, there were reductions in plasma levels of HIV-1 RNA of at least 96 percent (1.5 log) in seven of the eight study patients. Over the 6-month study period, replication of HIV-1 was controlled in two infants who began therapy at 2 1/2 months of age. Plasma RNA levels were reduced by 0.5 to 1.5 log in five of the other six infants.

CONCLUSIONS

Although further observations are needed, it appears that in infants with maternally acquired HIV-1 infection, combined treatment with zidovudine, didanosine, and nevirapine is well tolerated and has sustained efficacy against HIV-1.

Pharmacokinetics, safety, and activity of nevirapine in human immunodeficiency virus type 1-infected children

Phase I trials were conducted in human immunodeficiency virus type 1 (HIV-1)-infected children to examine the pharmacokinetics, safety, and antiretroviral activity of nevirapine, a nonnucleoside HIV-1 reverse transcriptase inhibitor. Nevirapine was rapidly absorbed, but the time to peak plasma concentrations increased with higher doses. Clearance was more rapid in chronic dosing studies than predicted by single-dose studies and was more rapid in younger children than in adolescent children. Rash, which occurred in 1 of the 21 study participants, was the single toxicity regarded as nevirapine-related. At doses > or = 240 mg/m2/day, 5 of 10 children experienced durable suppression of plasma p24 antigen to < 50% of baseline values through 8 weeks of nevirapine monotherapy. Viruses resistant to nevirapine were isolated from all children during therapy, but their isolation did not always predict loss of antiviral activity. The evaluation of nevirapine in combination therapy trials is underway in children.

Neonatal serologic screening and early treatment for congenital Toxoplasma gondii infection. The New England Regional Toxoplasma Working Group

BACKGROUND

Most infants with congenital Toxoplasma gondii infection have no symptoms at birth, but many will have retinal disease or neurologic abnormalities later in life. Early detection and treatment of congenital toxoplasmosis may reduce these sequelae.

METHODS

In Massachusetts since January 1986, and in New Hampshire since July 1988, newborns have been screened for intrauterine infection with T. gondii by means of an IgM capture immunoassay of blood specimens routinely collected for screening for metabolic disorders. Congenital infection is confirmed by assays for specific IgG and IgM antibodies in serum from infants and their mothers. For this study, infants with serologic evidence of infection underwent extensive clinical evaluation and received one year of treatment.

RESULTS

Through June 1992, 100 of 635,000 infants tested had positive screening tests. Congenital infection was confirmed in 52 infants, 50 of whom were identified only through neonatal screening and not through initial clinical examination. However, after the serologic results became available, more detailed examinations revealed abnormalities of either the central nervous system or the retina in 19 of 48 infants evaluated (40 percent). After treatment, only 1 of 46 children had a neurologic deficit (hemiplegia attributable to a cerebral lesion present at birth). Thirty-nine treated children had follow-up ophthalmologic examinations when one to six years old; four (10 percent) had eye lesions that may have developed postnatally (a macular lesion in one child and minor retinal scars in three).

CONCLUSIONS

Routine neonatal screening for toxoplasmosis identifies congenital infections that are subclinical, and early treatment may reduce the severe long-term sequelae.

Quantitation of human immunodeficiency virus in vertically infected infants and children

We used a quantitative human immunodeficiency virus, type 1 (HIV-1) culture method to determine whether there is a relationship between the amount of replicating virus in the blood of vertically infected children and the relatively short latency period before development of symptomatic disease in these children. HIV-1 titers were determined by end point dilution in the peripheral blood mononuclear cells and the plasma of 30 infected (CDC class P1 and P2), 36 indeterminate (CDC class PO), and 19 uninfected (CDC class P3) infants and children born to HIV-1 seropositive mothers. HIV-1 was recovered from 35 (90%) of 39 PBMC cultures and 23 (60%) of 38 plasma cultures of infected patients not receiving antiretroviral therapy. The mean HIV-1 titers tended to be higher in patients with more advanced disease (P2, D, E, or F: 1760 TCID/10(6) PBMC, 460 TCID/ml plasma) than in asymptomatic or mildly symptomatic patients (P1; P2, A or C: 90 TCID/10(6) PBMC; 60 TCID/ml plasma). A poor correlation between HIV-1 titers and serum p24 antigen levels was found. No correlation was observed between viral titers and relative or absolute numbers of CD4 lymphocytes. Plasma virus titers were lower in 9 patients receiving zidovudine (ZDV) therapy (mean 2 TCID/ml) than in untreated patients of similar clinical status. The viral titers measured in the blood of vertically infected infants and children were on the same order of magnitude as the viral titers measured in HIV-infected adults. We conclude that the relatively rapid progression to symptomatic disease of the majority of vertically infected patients is not due to a higher load of replicating virus in blood.

Infections in a pediatric intensive care unit

All infections occurring in a busy pediatric intensive care unit (PICU) from 1982 to 1984 were characterized by site, bacteriology, acquisition status, and outcome. Standard Centers for Disease Control criteria were employed. Nine hundred sixty-five patients were admitted to the PICU. Mortality was 3.4%. Two hundred twenty-one infections occurred in 180 patients. Infection rates were 23% and 6% for total and PICU-acquired infections, respectively. Infections of the central nervous system (n = 56), lower respiratory tract (n = 53), and genitourinary tract (n = 46) made up 70% of all infections. Haemophilus influenzae (n = 39) was the most commonly isolated pathogen. Staphylococcus aureus (20%) and Klebsiella-Enterobacter-Serratia (18.3%) were most commonly noted in PICU-acquired infections. Twenty infected patients (11.1%) died in the PICU. Lower respiratory tract infections (20.5%) were associated with the highest mortality. Both PICU-acquired and community-acquired infections were associated with similar mortalities. Infected patients in a PICU have a mortality approximately 300% higher than that seen in the overall PICU population. The data presented document the importance of infection and provide information against which similar units can gauge their infection status for quality-assurance purposes.