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Biomedical subjects

V A Johnson

Publications and source records attributed to V A Johnson.

At least 37 records · Page 2Linked to original sources
PubMed1998

CCR5/delta(ccr5) heterozygosity: a selective pressure for the syncytium-inducing human immunodeficiency virus type 1 phenotype. NIAID AIDS Clinical Trials Group Protocol 241 Virology Team.

Mechanisms underlying the delay in dominance of syncytium-inducing (SI) phenotype HIV-1 (human immunodeficiency virus type 1) in vivo are unknown. Both random mutational events and selective pressures operative only late in the disease process have been suggested to underlie the shift from CCR5 to alternative coreceptor usage. Among the moderately advanced patients who entered AIDS Clinical Trials Group protocol 241, SI viral phenotype was more common among CCRS/delta(ccr5) heterozygotes (7/7, 100%) than among CCR5/CCR5 homozygotes (29/88, 33%; P < .001, Fisher's exact test). Other characteristics did not differ at study entry by CCR5 genotype, including median CD4 cell counts, plasma RNA levels, and infectious HIV-1 titers in circulating cells. These data indicate that CCR5/delta(ccr5) heterozygosity, which decreases cell-surface levels of CCR5 available to serve as an HIV-1 entry coreceptor, is a selective pressure for evolution of T cell line-tropic viruses that use an alternative coreceptor.

Adult↗
PubMed1997

Monitoring plasma HIV-1 RNA levels in addition to CD4+ lymphocyte count improves assessment of antiretroviral therapeutic response. ACTG 241 Protocol Virology Substudy Team.

BACKGROUND: CD4+ lymphocyte counts and plasma HIV-1 RNA levels predict progression of HIV-related disease, but the relative importance of these and other virological factors in defining response to antiretroviral therapy is not yet clear. OBJECTIVE: To determine the short-term variability of plasma HIV-1 RNA level during stable therapy; the relative importance of pretreatment values and early changes in CD4+ count, HIV-1 RNA levels, and infectious HIV-1 titers in mononuclear cells of peripheral blood and pretreatment syncytium-inducing phenotype of an HIV-1 isolate for prediction of disease progression and decline in CD4+ counts during therapy. DESIGN: Data were collected prospectively in a randomized, clinical trial comparing two combination regimens (ACTG [AIDS Clinical Trials Group] Protocol 241) and pooled across treatments. SETTING: 8 AIDS Clinical Trials Units. PATIENTS: 198 adults with HIV-1 infection and no more than 350 CD4+ lymphocytes/mm3 who had received at least 6 months of nucleoside therapy. INTERVENTIONS: All patients received zidovudine and didanosine; 100 received nevirapine and 98 received placebo. MEASUREMENTS: CD4+ lymphocyte counts, plasma HIV-1 RNA levels, and infectious HIV-1 titers in cells were measured before and 8 and 48 weeks after study treatment. Assay for the syncytium-inducing viral phenotype was done at baseline. Progression was defined as occurrence of opportunistic infection, malignancy, or death during the 48 weeks after treatment began. RESULTS: The difference between two measurements of HIV-1 RNA levels at baseline was within +/-0.39 log10 copies/mL (2.5-fold) for 90% of 167 patients receiving stable therapy. In a multivariate model, risk for disease progression was reduced by 56% (95% CI, 8% to 79% [P = 0.028]) for every 10-fold lower HIV-1 RNA level at baseline, by 52% (CI, 6% increase to 79% reduction [P = 0.071]) for every 10-fold reduction in HIV-1 RNA level at 8 weeks after treatment initiation, and by 67% (CI, 42% to 81% [P < 0.001]) for every 2-fold higher CD4+ count at baseline. These risk factors and syncytium-inducing viral phenotype at baseline, but not infectious HIV-1 titers in circulating cells, were associated with change in CD4+ counts over 48 weeks. CONCLUSIONS: For an individual patient, a change in plasma HIV-1 RNA level of 2.5-fold or more probably indicates a true biological change. Monitoring HIV-1 RNA levels and CD4+ lymphocytes before a change in antiretroviral treatment and monitoring HIV-1 RNA levels shortly thereafter improves prediction of disease progression and decline in CD4+ counts for 1 year compared with monitoring CD4+ counts of HIV-1 RNA levels alone. Additional monitoring of infectious HIV-1 titers in mononuclear cells of peripheral blood is not useful.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Correspondence between the effect of zidovudine plus lamivudine on plasma HIV level/CD4 lymphocyte count and the incidence of clinical disease in infected individuals. North American Lamivudine HIV Working Group.

OBJECTIVES: To investigate whether apparently beneficial changes in plasma HIV RNA level and CD4 lymphocyte count that are induced by antiretroviral therapy are associated with a corresponding clinical benefit. METHODS: For 620 patients in two randomized, double-blind trials of lamivudine (3TC) and zidovudine (ZDV) plasma HIV RNA and CD4 lymphocyte count changes were compared in patients randomized to 3TC plus ZDV and patients randomized to other treatment arms. The effect of therapy on the HIV RNA level and CD4 count was compared with the effect of therapy on clinical endpoints over the same time period. RESULTS: Median baseline values for all subjects were 42 420 copies/ml for HIV RNA and 277 x 10(6)/l for CD4 count. During the trial a significantly lower HIV RNA level and higher CD4 count was sustained in the ZDV/3TC group compared with the other group, with a difference in the median area under the curve from baseline per month of follow-up of 0.38 log10 copies/ml HIV RNA and 0.18 log2 x 10(6)/l CD4 cells (P < 0.001 in each case). For patients who were initially asymptomatic or in CDC stage B, the adjusted relative hazard (RH) of AIDS for a twofold lower CD4 count was 3.14 [95% confidence interval (CI), 1.44-6.83] and for a 10-fold higher HIV RNA level was 3.22 (1.20-8.59). The RH progression to AIDS expected with ZDV/3TC compared with the control treatments, given the observed effects of treatment on CD4 cell counts and HIV RNA levels, is 0.52, whereas the observed value was 0.16 (0.03-0.74). After adjustment for HIV RNA and CD4 changes over time the observed RH of progression to AIDS for ZDV/3TC treatment compared with controls was increased to 0.36 and was no longer significant (95% CI, 0.07-1.85). CONCLUSION: In this analysis of two trials, the effects of ZDV/3TC in reducing plasma HIV RNA and raising peripheral blood CD4 counts were associated with concurrent clinical benefits and the effect of treatment on these markers could account for at least part of the clinical benefits of therapy that were observed.

Anti-HIV Agents↗
PubMed1997

How rural physicians compare on cost and quality measures for Medicaid ambulatory care episodes.

This study compares the costs and quality of episodes of care for two common childhood illnesses, urinary tract infections (UTI) and otitis media (OM), across providers practicing in rural, small town, and urban counties in Alabama in 1992. The data source is Medicaid claims data for children under age 8 who were treated for these conditions. The study found that episodes cared for by rural providers were less expensive than episodes cared for in other locations, both because fewer rural episodes included outpatient facility charges and because fewer ancillary services were provided in rural settings. Researchers also found that, even controlling for physician characteristics and patient demographic and utilization factors, rural episodes were significantly less likely to include two process measures of quality of care: fewer rural UTI episodes included urine cultures, and fewer rural OM episodes included follow-up visits. This study suggest that, as a group, rural physicians may have a favorable cost profile but a potentially unfavorable care content profile, compared with other physicians. Both practice profile data and explicit care recommendations need to be available to physicians so thy can monitor, defend, or alter their clinical practices.

Alabama↗
PubMed1997

Standardized peripheral blood mononuclear cell culture assay for zidovudine susceptibility testing of clinical human immunodeficiency virus type 1 isolates: effect of reducing the numbers of replicates and concentrations.

Zidovudine susceptibility was assessed for 525 clinical human immunodeficiency virus type 1 isolates, before and after reducing the number of replicates and zidovudine concentrations in the standardized consensus peripheral blood mononuclear cell culture assay. We conclude that omitting the 0.001 microM concentration and using duplicate rather than triplicate wells are valid and cost-effective modifications of this expensive assay.

Anti-HIV Agents↗
PubMed1997

Impact of care setting on cost and quality under Medicaid.

Medicaid claims data were used to compare the costs and care quality of ambulatory visits for two childhood illnesses, urinary tract infection (UTI) and suppurative otitis media (OM), in the fee-for-service Medicaid program in Alabama across three care settings: offices where patients had been seen before, offices where patients had not been seen before, and outpatient hospital departments. Forty percent of UTI visits and 46 percent of OM visits occurred in return office settings. Visits to outpatient hospital and first-time office settings were more expensive than those to return office settings, due to the billing of facility fees and the provision of additional services. Adherence to common measures of quality of care for both types of visits was low; 52 percent of UTI visits included urine cultures and 40 percent of OM visits included recheck visits. Adherence to these quality measures was significantly lower in visits occurring in hospital settings.

Alabama↗
PubMed1997

Comparison of inpatient charges between academic and nonacademic services in a children's hospital.

OBJECTIVE: To compare inpatient hospital charges generated within a children's hospital by academic and nonacademic pediatric services for common medical diagnoses. METHODS: Hospital admissions to a free-standing children's hospital between 9/1/90 and 8/30/94 were selected for patients who were hospitalized 1 to 14 days, with one of six selected diagnoses, and with discharge attending of record either a private pediatrician or an academic subspecialist. Discharge diagnoses, based on ICD-9 codes, included asthma (n = 1983), bronchiolitis (n = 692), gastroenteritis (n = 733), rule out sepsis (n = 1065), urinary tract infection (n = 516), and viral meningitis (n = 288). Charges associated with patient records were dichotomized as above or below the median charge for each diagnostic category. Each category was analyzed separately using a logistic regression model where the dichotomous-dependent variable was charges above the median charge for each diagnosis. Independent variables included physician type, payor status, patient residence, ICD-9 code as primary or secondary diagnosis, patient age, and presence of complicating conditions. RESULTS: By univariate comparison, academic physicians cared for a higher percentage of underinsured patients, and their care was more expensive. Complicated claims were associated with higher charges than uncomplicated claims for all diagnostic categories. Academic and nonacademic physicians were equally likely to generate above-median charges for five of the six diagnostic categories when controlling for confounding factors. A linear regression model in which charge was the dependent variable generated similar results. CONCLUSIONS: Within the same pediatric health care facility, no consistent difference was found between charges incurred on academic vs private inpatient services.

Alabama↗
PubMed1996

Lamivudine plus zidovudine compared with zalcitabine plus zidovudine in patients with HIV infection. A randomized, double-blind, placebo-controlled trial. North American HIV Working Party.

OBJECTIVE: To compare the safety and activity of lamivudine plus zidovudine with the safety and activity of zalcitabine plus zidovudine in patients with moderately advanced human immunodeficiency virus (HIV) infection who had received zidovudine. DESIGN: A multicenter, randomized, double-blind, three-arm, 24-week study with a blinded extension through at least 52 weeks. SETTING: 21 sites in the United States, Canada, and Puerto Rico. PATIENTS: 254 patients who had received zidovudine (median duration of previous therapy, 20 months) and had absolute CD4+ cell counts of 100 to 300 cells/mm3. INTERVENTIONS: Patients were randomly assigned to receive one of three regimens: 150 mg of lamivudine twice daily plus 200 mg of zidovudine three times daily (low-dose lamivudine group); 300 mg of lamivudine twice daily plus 200 mg of zidovudine three times daily (high-dose lamivudine group); or 0.75 mg of zalcitabine plus 200 mg of zidovudine three times daily (zalcitabine group). MEASUREMENTS: Immunologic activity was assessed primarily by changes in absolute CD4+ cell counts; virologic activity was assessed by changes in plasma HIV RNA levels as measured by reverse transcriptase polymerase chain reaction. Safety of the treatment regimens was assessed through the reporting of adverse events. RESULTS: 78% of patients completed 24 weeks of study treatment, and 63% of patients completed 52 weeks of study treatment. Changes in absolute CD4+ cell counts were significantly better for the low-dose and the high-dose lamivudine groups than for the zalcitabine group (median changes at 52 weeks were +42.5 cells/mm3 in the low-dose lamivudine group, +23.33 cells/mm3 in the high-dose lamivudine group, and -29.58 cells/mm3 in the zalcitabine group). Suppression of plasma HIV RNA levels was similar for all groups (median changes at 52 weeks were -0.48 log10 copies/mL in the low-dose lamivudine group, -0.51 log10 copies/mL in the high-dose lamivudine group, and -0.39 log10 copies/mL in the zalcitabine group). No significant differences in safety were seen among the three regimens, although the low-dose lamivudine regimen appeared to be better tolerated than the others. CONCLUSIONS: In patients with HIV infection who had previously received zidovudine, 150 mg of lamivudine plus zidovudine resulted in greater immunologic evidence of benefit than did 0.75 mg of zalcitabine plus zidovudine and was better tolerated than 300 mg of lamivudine plus zidovudine.

Adult↗
PubMed1996

Nevirapine, zidovudine, and didanosine compared with zidovudine and didanosine in patients with HIV-1 infection. A randomized, double-blind, placebo-controlled trial. National Institute of Allergy and Infectious Diseases AIDS Clinical Trials Group Protocol 241 Investigators.

OBJECTIVE: To study the addition of a third human immunodeficiency virus type 1 (HIV-1) reverse transcriptase inhibitor, nevirapine, to the combination of zidovudine and didanosine. DESIGN: A 48-week, randomized, double-blind, placebo-controlled trial at 16 AIDS (acquired immunodeficiency syndrome) Clinical Trials Units. PATIENTS: 398 adults who had HIV-1 infection, had 350 or fewer CD4+ T lymphocytes/mm3, and had had more than 6 months of previous nucleoside therapy. INTERVENTION: 1) Either nevirapine or placebo (200 mg/d for 2 weeks, then 400 mg/d thereafter) and 2) open-label zidovudine (600 mg/d) and didanosine (400 mg/d for patients weighing > or = 60 kg). MEASUREMENTS: CD4+ T lymphocyte counts, time to first HIV-1 disease progression event or death, adverse events, and nevirapine levels in plasma samples taken at random were measured in all patients. Plasma levels of HIV-1 RNA HIV-1 infectivity titer in peripheral blood mononuclear cells; serum p24 antigen levels; and plasma levels of zidovudine and didanosine were measured in patients enrolled at half the study sites. RESULTS: After 48 weeks of study treatment the patients assigned to the triple-combination regimen (nevirapine, zidovudine, and didanosine) had an 18% higher mean absolute CD4 cell count (95% Cl, 7% to 29%; P = 0.001), a 0.32 log10 lower mean infectious HIV-1 titer in peripheral blood mononuclear cells (Cl, 0.05 to 0.59 log10 infectious units per million cells; P = 0.023), and a 0.25 log10 lower mean plasma HIV-1 RNA level (Cl, 0.03 to 0.48 log10 RNA copies/mL; P = 0.028) than did patients assigned to the double-combination regimen (zidovudine and didanosine). Severe rashes were more common among patients assigned to receive the triple combination (9% compared with 2%; P = 0.002). Risk for disease progression did not differ between the two groups (relative hazard of the triple-combination group, 1.24 [Cl, 0.75 to 2.06]; P > 0.2), although the study had only moderate power to detect a major difference. CONCLUSIONS: Adding nevirapine to zidovudine and didanosine improved the long-term immunologic and virologic effects of therapy and was associated with severe rash among the patients studied, who had had extensive previous therapy. These results support 1) the continuing development of combinations of more than two antiretroviral drugs to increase and prolong HIV-1 suppression and 2) the potential utility of nevirapine in combination regimens.

Adult↗
PubMed1996

Prognostic value of plasma human immunodeficiency virus type 1 (HIV-1) RNA levels in patients with advanced HIV-1 disease and with little or no prior zidovudine therapy. AIDS Clinical Trials Group Protocol 116A/116B/117 Team.

The association of plasma human immunodeficiency virus type 1 (HIV-1) RNA level at study entry and over time with clinical progression was evaluated in 187 patients from AIDS Clinical Trials Group protocol 116A who had little or no prior zidovudine treatment. Three-fold-higher HIV-1 RNA levels at study entry and 3-fold increases by week 8 were associated with progression (relative hazard [RH], 1.67; 95% confidence limits [CL], 1.20, 2.32; and RH, 1.45; CL, 1.02, 2.05, respectively). Having 3-fold-higher CD4 cell count at entry was independently associated with a 52% reduction in risk for progression (adjusted RH, 0.48; CL, 0.33, 0.70). When stratified by length of prior zidovudine therapy, RNA level was predictive in drug-naive patients (adjusted RH, 1.87; CL, 1.23, 2.85) but not predictive in patients with up to 16 weeks of prior therapy (adjusted RH, 1.11; CL, 0.70, 1.76). Analysis suggests that the acquisition of mutations at HIV-1 reverse transcriptase codons 215 and 74 is associated with subsequent increases in HIV-1 RNA level (relative risk, 7.00; CL, 0.86, 56.90).

Acquired Immunodeficiency Syndrome↗
PubMed1996

Association of plasma human immunodeficiency virus type 1 RNA level with risk of clinical progression in patients with advanced infection. AIDS Clinical Trials Group (ACTG) 116B/117 Study Team. ACTG Virology Committee Resistance and HIV-1 RNA Working Groups.

Human immunodeficiency virus (HIV)-1 RNA level in plasma was evaluated as a surrogate marker for disease progression in a clinical trial of advanced HIV-1 infection. Baseline HIV-1 RNA level was an independent predictor of disease progression (relative hazard [RH] for each doubling of HIV-1 RNA level, 1.26; 95% confidence interval [CI], 1.03-1.54; P = .02), after adjusting for the week 4 change in HIV-1 RNA level, baseline CD4 cell count, syncytium-inducing phenotype, clinical status at study entry, and therapy randomization. A 50% reduction in HIV-1 RNA level was associated with a 27% decrease in the adjusted risk of disease progression during the study (RH, 0.73; 95% CI, 0.52-1.02; P = .07). The partial validation of HIV-1 RNA as a predictor for clinical end points has implications for the use of HIV-1 RNA in clinical trials and practice.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Patient's choice of hospital or office for Medicaid ambulatory care in Alabama.

The primary policy option that has been suggested to states over the years for shifting care for Medicaid beneficiaries away from hospital sites and toward office sites has been to raise Medicaid fees to physicians on the assumption that this increases the geographic availability of office-based care, which then naturally attracts Medicaid clients away from hospital sites. This study uses Medicaid claims data from the state of Alabama to assess the role of geographic provider availability relative to other factors in families' decisions to select a hospital or an office for an illness visit to a primary care or to a specialist physician. The authors examined the last ambulatory visit for an illness made by continuously enrolled children under age 8 in the first half of 1991. The authors found that both higher Medicaid office practice density and the presence of larger Medicaid office practices were associated with choice of an office for ambulatory care, whereas the presence of larger Medicaid hospital practices were associated with choice of a hospital for care. Controlling for provider availability, hospital users were less likely to have sought previous care for illness during the year, and were more likely to be rural residents, to have traveled away from their home counties for care, and to be eligible for Medicaid through Aid to Families with Dependent Children, rather than through the program's income expansions. We conclude that increased office-based provider availability must be coupled with improved access tor new, remote, and very low income families if Medicaid clients are to be expected to voluntarily shift their choice if site for ambulatory care.

Alabama↗
PubMed1995

Zidovudine resistance and HIV-1 disease progression during antiretroviral therapy. AIDS Clinical Trials Group Protocol 116B/117 Team and the Virology Committee Resistance Working Group.

OBJECTIVE: To evaluate the association between resistance of human immunodeficiency virus type 1 (HIV-1) to zidovudine and clinical progression. DESIGN: Retrospective analysis of specimens from patients in the AIDS Clinical Trials Group (ACTG) protocol 116B/117, a randomized comparison of didanosine with continued zidovudine therapy in patients with advanced HIV-1 disease who had received 16 weeks or more of previous zidovudine therapy. SETTING: Participating ACTG virology laboratories. PATIENTS: 187 patients with baseline HIV-1 isolates. MEASUREMENTS: Zidovudine susceptibility testing and assays for syncytium-inducing phenotype were done on baseline HIV-1 isolates. Relative hazards for clinical progression or death associated with baseline clinical, virologic, and immunologic factors were determined from Cox proportional hazards regression models. RESULTS: Compared with other patients, 15% (26 of 170) with isolates showing high-level zidovudine resistance (50% inhibitory zidovudine concentration > or = 1.0 microM) had 1.74 times the risk for progressing to a new AIDS-defining event or death (95% CI, 1.00 to 3.03) and 2.78 times the risk for death (CI, 1.21 to 6.39) in analyses that controlled for baseline CD4+ T-lymphocyte count, syncytium-inducing HIV-1 phenotype, disease stage, and randomized treatment assignment. The clinical benefit of didanosine was not limited to patients with highly zidovudine-resistant baseline HIV-1 isolates. CONCLUSIONS: High-level resistance of HIV-1 to zidovudine predicted more rapid clinical progression and death when adjusted for other factors. However, patients with advanced HIV-1 disease may benefit from a change in monotherapy from zidovudine to didanosine whether high-level HIV-1 resistance to zidovudine is present or absent, and laboratory assessment of zidovudine resistance is not necessary for deciding when to switch monotherapy from zidovudine to didanosine.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Viral dynamics in human immunodeficiency virus type 1 infection.

The dynamics of HIV-1 replication in vivo are largely unknown yet they are critical to our understanding of disease pathogenesis. Experimental drugs that are potent inhibitors of viral replication can be used to show that the composite lifespan of plasma virus and virus-producing cells is remarkably short (half-life approximately 2 days). Almost complete replacement of wild-type virus in plasma by drug-resistant variants occurs after fourteen days, indicating that HIV-1 viraemia is sustained primarily by a dynamic process involving continuous rounds of de novo virus infection and replication and rapid cell turnover.

Antiviral Agents↗
PubMed1995

Prevalence and clinical significance of zidovudine resistance mutations in human immunodeficiency virus isolated from patients after long-term zidovudine treatment. AIDS Clinical Trials Group 116B/117 Study Team and the Virology Committee Resistance Working Group.

Zidovudine resistance mutations at reverse transcriptase codons 215 or 41 were found in two-thirds of human immunodeficiency virus type 1 (HIV-1) isolates obtained at baseline from patients enrolled in an AIDS Clinical Trials Group (ACTG) protocol that compared didanosine with continued zidovudine in patients with > or = 16 weeks of previous zidovudine therapy (ACTG 116B/117). The combined presence of mutations at both codons 215 and 41 conferred an increased risk for progression (relative hazard, 1.82; 95% confidence interval [CI], 1.02-3.26) and an increased risk for death (RH, 5.42; 95% CI, 1.92-15.30) in analyses that controlled for other factors predictive of progression. However, the benefit of switching to didanosine compared with continued zidovudine therapy was independent of the presence of these mutations. Although this information is not helpful in determining when to alter therapy, detection of zidovudine resistance mutations provides prognostic information in patients with advanced HIV disease.

Adult↗
PubMed1995

Nucleoside reverse transcriptase inhibitors and resistance of human immunodeficiency virus type 1.

Drug-resistant isolates of human immunodeficiency virus type 1 (HIV-1) emerge during long-term treatment with nucleoside reverse transcriptase inhibitors, such as zidovudine. The clinical significance of in vitro drug resistance to zidovudine has been difficult to determine. However, in a virologic analysis of baseline specimens from the AIDS Clinical Trials Group (ACTG) 116B/117 study, high-level zidovudine resistance, defined as an IC50 of > or = 1 microM at study entry, was significantly associated with clinical disease progression. High-level zidovudine resistance also was an independent predictor of death as an end point, although this finding does not imply a direct causal effect. Duration and cumulative dose of prior zidovudine therapy did not predict clinical disease progression. More potent antiretroviral agents are needed that can be used in combination to achieve more complete virus suppression and to reduce the selection of drug-resistant HIV-1 mutants.

Clinical Trials as Topic↗
PubMed1995

Patterns of care received by Medicaid recipients with urinary tract infections.

BACKGROUND: Urinary tract infections (UTIs) occur commonly in children and may lead to substantial morbidity. Most experts recommend urine cultures for diagnosing UTIs in children. In addition, most experts recommend imaging studies in a portion of children diagnosed with UTIs. PURPOSE: The purpose of this study was to assess how rates of performance of urine cultures and imaging studies for children in the Alabama Medicaid program diagnosed with a UTI vary by patient demographics, provider characteristics, and service locations. METHODS: The study design was a retrospective review of Alabama Medicaid claims data. Children were included as UTI cases if they had a Medicaid claim for urinary tract infections during 1991, were continuously enrolled in Medicaid for that year, and were younger than 8 years of age. Claims were grouped into episodes of care, and episodes were assigned to a diagnosing physician. Physician locations were classified as rural, suburban, or urban using demographic data. Specific laboratory and imaging procedures were identified using CPT codes (Physician's Current Procedural Technology Codes, 4th Edition). RESULTS: We identified 404 episodes of UTI occurring in 380 children. Only 47% of episodes were associated with claims for urine cultures. Claims for urine cultures were more frequently filed by pediatricians in urban locations. In the subset of 114 patients with multiple UTI episodes, only 68% had imaging studies specific for the urinary tract. Only 44% received both a voiding cystourethrogram and renal ultrasound. CONCLUSIONS: Claims data suggest that physicians underuse urine cultures in diagnosing UTIs in Alabama pediatric Medicaid recipients. Urban-based pediatricians perform better than other types of physicians. Imaging studies are also used less frequently than is commonly recommended.

Alabama↗