What can technology do to, and for, family medicine?

Medical technology can be divided into information technology, diagnostic technology, and therapeutic technology. These technologies can enhance the care of patients in a family practice; they also have the potential to diminish or fragment family practice when the technologies can only be provided by specialists. While some family physicians have an aversion to technological advances, we believe it is imperative that family physicians participate in the development of technologies that enhance family practice and improve patient outcomes in primary care practice. These include electronic medical records, decision support systems, tools for managing medical information, and others. Criteria are presented to help determine when these new technologies should be adopted into practice.

Refractory mucosal candidiasis in advanced human immunodeficiency virus infection

We conducted a multicenter, prospective study of the risk factors, natural history, and outcome of fluconazole-refractory mucosal candidiasis (FRMC) in 832 persons with advanced human immunodeficiency virus (HIV) infection (median CD4 cell count, 14/mm3) during 1994-1996. FRMC was defined as mucosal candidiasis that failed to resolve despite 14 days of therapy with daily doses (> or =200 mg) of fluconazole. Thirty-six persons (4.3%) had FRMC (35, oral; 1, esophageal), for an incidence of 4.2 per 100 person-years (859.7 total years of follow-up). In a multivariate model, the use of trimethoprim-sulfamethoxazole within 6 months of enrollment (relative risk [RR], 2.39; P=.04) and the use of fluconazole daily or every other day (RR, 5.64; P=.004) were significantly associated with the development of FRMC. The median survival after the development of FRMC was 32.6 weeks. In conclusion, the annual incidence of FRMC was <5%. Refractory candidiasis was a poor prognostic indicator. Daily or every-other-day use of fluconazole was associated with the development of refractory infection.

A randomized trial of interferon alpha therapy for HIV type 1 infection

The immunologic and virologic efficacy and safety of interferon a (IFN-alpha) administered in combination with zidovudine (ZDV) and zalcitabine (ddC) was evaluated in HIV-infected subjects with CD4+ cell counts between 300 and 500 cells/ml and no more than 14 weeks of prior antiretroviral therapy. A total of 256 subjects enrolled in an open-label, randomized controlled trial. Subjects were randomized equally into treatment groups. All subjects received ZDV and ddC, while half also receive IFN-alpha (3 MU subcutaneously every 24 hr). At 48 weeks the median average area under the curve minus baseline (AAUCMB) for plasma HIV-1 RNA for the two-drug group was -0.68 versus -0.75 log10 copies/ml for the IFN-alpha group (p = 0.046). Mean HIV-1 RNA changes from baseline to 48 weeks for these groups were -0.65 and -1.12 log10 copies/ml, respectively (p = 0.010). The median AAUCMB for CD4+ cell count for the two-drug group was 28 versus -1 cells/mm3 for the IFN-alpha group (p = 0.011). Neutropenia, anemia, and drug intolerance were more common in the IFN-alpha group. This study demonstrates that IFN-alpha inhibits HIV-1 replication but attenuates the CD4+ cell response to dual therapy with ZDV and ddC.

Utility of urine and leukocyte cultures and plasma DNA polymerase chain reaction for identification of AIDS patients at risk for developing human cytomegalovirus disease

Urine and blood leukocyte cultures and qualitative plasma polymerase chain reaction (PCR) and quantitative competitive (QC) PCR were evaluated for their ability to identify AIDS patients at risk for human cytomegalovirus (HCMV) disease. AIDS patients were followed with urine and blood specimens every 3 months. During a mean follow-up of 12 months, 26 (28%) developed HCMV disease. The sensitivity, specificity, positive predictive value, and negative predictive value for urine culture were 85%, 29%, 31%, and 83%; for leukocyte culture were 38%, 74%, 69%, and 81%; for qualitative plasma PCR were 89%, 75%, 58%, and 94%; for QC-PCR (>1000 copies/microL) were 35%, 100%, 100%, and 80%; and for QC-PCR (>100 copies/microL) were 73%, 90%, 73%, and 90%, respectively. Of 41 patients identified by qualitative PCR to have HCMV DNA in plasma, the 24 who developed HCMV disease had 1510 +/- 448 (mean +/- SE) peak copies of HCMV DNA/microL by QC-PCR, versus 161 +/- 52 for the 17 patients who did not develop disease (P = .0007). Thus, plasma PCR is superior to culture for identification of AIDS patients at risk for HCMV disease, and quantitation of plasma DNA further identifies high-risk persons.

Serum chemokine levels in patients with non-progressing HIV infection

OBJECTIVE

To evaluate serum chemokines, macrophage inflammatory protein (MIP)-1 alpha, MIP-1 beta and RANTES, concentrations in non-progressing HIV-infected patients and AIDS patients.

SETTING

University Hospital-based AIDS Clinical Trials Unit.

DESIGN/METHODS

Serum MIP-1 alpha, MIP-1 beta and RANTES levels were determined by enzyme-linked immunosorbent assay using archived serum specimens obtained on two occasions at least 1.8 years apart.

PATIENT SELECTION

Long-term non-progressing HIV-infected adult patients were identified from clinic records. For each non-progressing patient two adult AIDS patients with initial documentation of seropositivity the same year and the same length of follow-up were selected.

RESULTS

Four long-term non-progressing patients and eight AIDS patients were studied. Neither the duration of known HIV positivity at the time of specimen collection nor the length of time between specimen collections differed significantly between non-progressing patients and AIDS patients. Serum levels of MIP-1 alpha, MIP-1 beta and RANTES in specimens obtained either early or later in the course of HIV infection did not differ significantly between non-progressing patients and AIDS patients. In the two patient subsets, significant differences in serum chemokine levels over time were not observed. The rate of change of serum chemokine concentration over time also did not differ between non-progressing patients and AIDS patients. Serum MIP-1 alpha and MIP-1 beta levels did not reach levels reported to suppress HIV proliferation in vitro. When expressed as a quantity per peripheral blood CD8+ lymphocyte, AIDS patients exhibited significantly greater levels of MIP-1 alpha, MIP-1 beta and RANTES than non-progressing HIV patients (P < 0.05). These values did not exhibit a significant variation over time.

CONCLUSIONS

Serum MIP-1 alpha, MIP-1 beta and RANTES levels do not distinguish patients with AIDS from patients with non-progressing HIV infection. Variations in levels of these chemokines do not explain individual variation in the natural history of HIV infection.

Comparison of three regimens for treatment of mild to moderate Pneumocystis carinii pneumonia in patients with AIDS. A double-blind, randomized, trial of oral trimethoprim-sulfamethoxazole, dapsone-trimethoprim, and clindamycin-primaquine. ACTG 108 Study Group

OBJECTIVE

To compare the tolerability and efficacy of three oral regimens for the treatment of patients with the acquired immunodeficiency syndrome (AIDS) and Pneumocystis carinii pneumonia.

DESIGN

A randomized, double-blind study.

SETTING

24 U.S. academic medical centers.

PATIENTS

181 patients with morphologically confirmed P. carinii pneumonia and alveolar-arterial oxygen differences (PAO2-PaO2) of 45 mm Hg or less.

INTERVENTION

Patients were randomly assigned to receive trimethoprim-sulfamethoxazole, dapsone-trimethoprim, or clindamycin-primaquine for 21 days. Patients with a PAO2-PaO2 of 35 to 45 mm Hg at study entry also received prednisone.

MEASUREMENTS

Serial clinical and laboratory evaluations for therapeutic response and toxicity. Therapeutic failure at day 21 was defined by any of the following: increase in PAO2-PaO2 of greater than 20 mm Hg; no remission of baseline signs and symptoms; and change in antipneumocystis therapy for reasons other than toxicity, intubation, or death. Dose-limiting toxicity was defined as discontinuation of therapy by the primary physician because of one or more adverse reactions.

RESULTS

No statistically significant differences were seen among treatment groups in the proportions of patients who had dose-limiting toxicity (P=0.2), therapeutic failure (P>0.2), or a complete course of therapy (P>0.2). Survival during therapy or for 2 months thereafter did not differ among the three groups (P>.02). However, elevation of serum aminotransferase levels to more than five times the baseline levels was more frequent in the trimethoprim-sulfamethoxazole group (P=0.003), and one or more serious hematologic toxicities (neutropenia, anemia, thrombocytopenia, or methemoglobinemia) occurred more frequently in the clindamycin-primaquine group (P=0.01).

CONCLUSIONS

The rates of dose-limiting toxicity, therapeutic failure, and survival did not differ among patients with AIDS who were receiving oral trimethoprim-sulfamethoxazole, dapsone-trimethoprim, or clindamycin-primaquine for mild to moderate P. carinii pneumonia. However, the limited sample size prevents the unequivocal demonstration of the equality of these three regimens. Differences in expected categories of toxicities associated with each regimen should guide the clinician in choosing first-line therapy, particularly for patients with baseline hepatic insufficiency or myelosuppression.

A randomized trial of three antipneumocystis agents in patients with advanced human immunodeficiency virus infection. NIAID AIDS Clinical Trials Group

BACKGROUND

We evaluated the effectiveness of three treatment strategies for the prevention of a first episode of Pneumocystis carinii pneumonia in patients infected with the human immunodeficiency virus (HIV).

METHODS

In an open-label trial, 843 patients with HIV infection and fewer than 200 CD4+ cells per cubic millimeter received zidovudine plus one of three randomly assigned prophylactic agents, beginning with trimethoprim-sulfamethoxazole, dapsone, or aerosolized pentamidine and followed by a defined sequence of other drugs to be used in cases of intolerance.

RESULTS

The estimated 36-month cumulative risks of P. carinii pneumonia were 18 percent, 17 percent, and 21 percent in the trimethoprim-sulfamethoxazole, dapsone, and aerosolized-pentamidine groups, respectively (P = 0.22). The difference in risk among treatment strategies was negligible in patients entering the study with 100 or more CD4+ lymphocytes per cubic millimeter. In those entering with fewer than 100 CD4+ cells per cubic millimeter, the risk was 33 percent with aerosolized pentamidine, as compared with 19 percent with trimethoprim-sulfamethoxazole and 22 percent with dapsone (P = 0.04). The lowest failure rates occurred in patients receiving trimethoprim-sulfamethoxazole, and failures were more common with 50 mg of dapsone than with 100 mg. Toxoplasmosis developed in less than 3 percent of patients. Of the patients assigned to the two systemic therapies, only 23 percent were receiving their assigned drug and dose when they completed the study. The median survival was approximately 39 months in all three groups, and the mortality attributable to P. carinii pneumonia was only 1 percent.

CONCLUSIONS

In patients with advanced HIV infection, the three treatment strategies we examined have similar effectiveness in preventing P. carinii pneumonia. Strategies that start with trimethoprim-sulfamethoxazole or with high-dose dapsone, rather than aerosolized pentamidine, are superior in patients with fewer than 100 CD4+ lymphocytes per cubic millimeter.

A randomized trial comparing fluconazole with clotrimazole troches for the prevention of fungal infections in patients with advanced human immunodeficiency virus infection. NIAID AIDS Clinical Trials Group

BACKGROUND

Cryptococcal meningitis and other serious fungal infections are common complications in patients infected with the human immunodeficiency virus (HIV). Fluconazole is effective for long-term suppression of many fungal infections, but its effectiveness as primary prophylaxis had not been adequately evaluated.

METHODS

We conducted a prospective, randomized trial that compared fluconazole (200 mg per day) with clotrimazole troches (10 mg taken five times daily) in patients who were also participating in a randomized trial of primary prophylaxis for Pneumocystis carinii pneumonia.

RESULTS

After a median follow-up of 35 months, invasive fungal infections had developed in 4.1 percent of the patients in the fluconazole group (9 of 217) and in 10.9 percent of those in the clotrimazole group (23 of 211; relative hazard, as adjusted for the CD4+ count, 3.3; 95 percent confidence interval, 1.5 to 7.6). Of the 32 invasive fungal infections, 17 were cryptococcosis (2 in the fluconazole group and 15 in the clotrimazole group; adjusted relative hazard, 8.5; 95 percent confidence interval, 1.9 to 37.6). The benefit of fluconazole was greater for the patients with 50 or fewer CD4+ cells per cubic millimeter than for the patients with higher counts. Fluconazole was also effective in preventing esophageal candidiasis (adjusted relative hazard, 5.8; 95 percent confidence interval, 1.7 to 20.0; P = 0.004) and confirmed and presumed oropharyngeal candidiasis (5.7 and 38.1 cases per 100 years of follow-up in the fluconazole and clotrimazole groups, respectively; P < 0.001). Survival was similar in the two groups.

CONCLUSIONS

Fluconazole taken prophylactically reduces the frequency of cryptococcosis, esophageal candidiasis, and superficial fungal infections in HIV-infected patients, especially those with 50 or fewer CD4+ lymphocytes per cubic millimeter, but the drug does not reduce overall mortality.

Macrophages from human immunodeficiency virus-positive persons are defective in host defense against Histoplasma capsulatum

The phagocytic and fungistatic activity of monocyte-derived macrophages from human immunodeficiency virus (HIV)-positive persons against Histoplasma capsulatum yeasts was determined. Macrophages from HIV-positive patients were profoundly deficient in their capacity to recognize and bind H. capsulatum, but ingestion of bound yeasts was normal. The binding of H. capsulatum by patient macrophages tended to decrease with a decrease in CD4+ T lymphocyte counts. Another major defect was that patient macrophages were more permissive for the intracellular growth of H. capsulatum. Macrophages from 22 of 58 patients showed a > or = 2-fold increase in intracellular growth compared with control macrophages. Thus, in addition to defects in cell-mediated immunity caused by a loss of CD4+ T cells, macrophages from HIV-positive patients exhibit intrinsic defects in macrophage function against H. capsulatum that may contribute to the increased susceptibility of HIV-positive patients to disseminated histoplasmosis.

Trimetrexate with leucovorin versus trimethoprim-sulfamethoxazole for moderate to severe episodes of Pneumocystis carinii pneumonia in patients with AIDS: a prospective, controlled multicenter investigation of the AIDS Clinical Trials Group Protocol 029/031

Trimetrexate is a powerful inhibitor of the dihydrofolate reductase of Pneumocystis carinii. AIDS patients (n = 215) with moderate to severe P. carinii pneumonia were enrolled in a double-blind study of trimetrexate plus leucovorin versus trimethoprim-sulfamethoxazole (TMP-SMZ) for 21 days. By study day 10, study therapy failed because of lack of efficacy in 16% of patients assigned to TMP-SMZ and 27% assigned to trimetrexate (P = .064), and the PAO2-PaO2 improved significantly faster with TMP-SMZ. By study day 21, failure rates were 20% with TMP-SMZ and 38% with trimetrexate (P = .008), with respective mortality rates of 12% and 20% (P = .088). By study day 49, the difference in mortality (16% vs. 31%) was significant (P = .028). The cumulative incidence of serious and treatment-terminating adverse events including hematologic toxicities was less with trimetrexate (P < .001). Thus, trimetrexate plus leucovorin was effective, albeit inferior to TMP-SMZ, for moderately severe P. carinii pneumonia but was better tolerated than TMP-SMZ.

Comparison of atovaquone (566C80) with trimethoprim-sulfamethoxazole to treat Pneumocystis carinii pneumonia in patients with AIDS

BACKGROUND

Both trimethoprim-sulfamethoxazole and pentamidine are effective as treatments for Pneumocystis carinii pneumonia, but adverse effects frequently limit their use. Atovaquone (566C80) is a new hydroxynaphthoquinone with activity against P. carinii.

METHODS

We conducted a double-blind, multicenter study in patients with the acquired immunodeficiency syndrome and mild or moderately severe P. carinii pneumonia. They were randomly assigned to 21 days of orally administered treatment three times daily with either atovaquone (750 mg) or trimethoprim (320 mg) plus sulfamethoxazole (1600 mg).

RESULTS

Of the 322 patients with histologically confirmed P. carinii pneumonia, 160 received atovaquone and 162 received trimethoprim-sulfamethoxazole. Of those who could be evaluated for therapeutic efficacy, 28 of 138 patients given atovaquone (20 percent) and 10 of 146 patients given trimethoprim-sulfamethoxazole (7 percent) did not respond (P = 0.002). Treatment-limiting adverse effects required a change of therapy in 11 patients in the atovaquone group (7 percent) and 33 patients in the trimethoprim-sulfamethoxazole group (20 percent) (P = 0.001). Therapy involving only the initial drug was successful and free of adverse effects in 62 percent of those assigned to atovaquone and 64 percent of those assigned to trimethoprim-sulfamethoxazole. Within four weeks of the completion of treatment, there were 11 deaths in the atovaquone group (4 due to P. carinii pneumonia) and 1 death in the trimethoprim-sulfamethoxazole group (P = 0.003). Diarrhea at entry was associated with lower plasma drug concentrations (P = 0.009), therapeutic failure (P < 0.001), and death (P < 0.001) in the atovaquone group but not in the trimethoprim-sulfamethoxazole group.

CONCLUSIONS

For the treatment of P. carinii pneumonia, atovaquone is less effective than trimethoprim-sulfamethoxazole, but it has fewer treatment-limiting adverse effects.

Cooling effects and comfort of four cooling blanket temperatures in humans with fever

Adult patients with fever (N = 89) were randomized into four blanket temperature groups: 7.2, 12.8, 18.3, and 23.9 degrees C. With their extremities protected, subjects were given acetaminophen and placed between two cooling blankets. There were no differences in the mean time (in minutes) to cool to a body temperature of 38.9 degrees C among groups. Although there were no differences in mean time for shivering, a trend of less shivering was apparent with warmer blanket temperatures. Few patients shivered (n = 17). There were no differences in the mean time (in minutes) for afterfall among the groups. The mean amount of afterfall for the 7.2 degrees C group (1.04 degrees C, SD = 0.50) was significantly greater than the 23.9 degrees C group (0.68 degrees C, SD = 0.47). Comfort scores significantly improved with warmer blanket temperatures. Thus, warmer blanket temperatures provided similar rates of cooling as the colder temperatures, yet were perceived to be more comfortable by the patient.