Chest radiography for predicting the cause of febrile illness among inpatients in Moshi, Tanzania

AIM

To describe chest radiographic abnormalities and assess their usefulness for predicting causes of fever in a resource-limited setting.

MATERIALS AND METHODS

Febrile patients were enrolled in Moshi, Tanzania, and chest radiographs were evaluated by radiologists in Tanzania and the United States. Radiologists were blinded to the results of extensive laboratory evaluations to determine the cause of fever.

RESULTS

Of 870 febrile patients, 515 (59.2%) had a chest radiograph available; including 268 (66.5%) of the adolescents and adults, the remainder were infants and children. One hundred and nineteen (44.4%) adults and 51 (20.6%) children were human immunodeficiency virus (HIV)-infected. Among adults, radiographic abnormalities were present in 139 (51.9%), including 77 (28.7%) with homogeneous and heterogeneous lung opacities, 26 (9.7%) with lung nodules, 25 (9.3%) with pleural effusion, 23 (8.6%) with cardiomegaly, and 13 (4.9%) with lymphadenopathy. Among children, radiographic abnormalities were present in 87 (35.2%), including 76 (30.8%) with homogeneous and heterogeneous lung opacities and six (2.4%) with lymphadenopathy. Among adolescents and adults, the presence of opacities was predictive of Streptococcus pneumoniae and Coxiella burnetii, whereas the presence of pulmonary nodules was predictive of Histoplasma capsulatum and Cryptococcus neoformans.

CONCLUSIONS

Chest radiograph abnormalities among febrile inpatients are common in northern Tanzania. Chest radiography is a useful adjunct for establishing an aetiologic diagnosis of febrile illness and may provide useful information for patient management, in particular for pneumococcal disease, Q fever, and fungal infections.

PEG1/MEST and IGF2 DNA methylation in CIN and in cervical cancer

INTRODUCTION

Although most invasive cervical cancer (ICC) harbor <20 human papillomavirus (HPV) genotypes, use of HPV screening to predict ICC from HPV has low specificity, resulting in multiple and costly follow-up visits and overtreatment. We examined DNA methylation at regulatory regions of imprinted genes in relation to ICC and its precursor lesions to determine if methylation profiles are associated with progression of HPV-positive lesions to ICC.

MATERIALS AND METHODS

We enrolled 148 controls, 38 CIN and 48 ICC cases at Kilimanjaro Christian Medical Centre from 2008 to 2009. HPV was genotyped by linear array and HIV-1 serostatus was tested by two rapid HIV tests. DNA methylation was measured by bisulfite pyrosequencing at regions regulating eight imprinted domains. Logistic regression models were used to estimate odd ratios.

RESULTS

After adjusting for age, HPV infection, parity, hormonal contraceptive use, and HIV-1 serostatus, a 10 % decrease in methylation levels at an intragenic region of IGF2 was associated with higher risk of ICC (OR 2.00, 95 % CI 1.14-3.44) and cervical intraepithelial neoplasia (CIN) (OR 1.51, 95 % CI 1.00-2.50). Methylation levels at the H19 DMR and PEG1/MEST were also associated with ICC risk (OR 1.51, 95 % CI 0.90-2.53, and OR 1.44, 95 % CI 0.90-2.35, respectively). Restricting analyses to women >30 years further strengthened these associations.

CONCLUSIONS

While the small sample size limits inference, these findings show that altered DNA methylation at imprinted domains including IGF2/H19 and PEG1/MEST may mediate the association between HPV and ICC risk.

Nest-site fidelity in parental male bluegill Lepomis macrochirus: spatial patterns and the influence of prior mating success

A 4 year mark-recapture study examined the pattern of nesting site fidelity of parental-type male bluegill Lepomis macrochirus. The study results indicated that iteroparous male L. macrochirus choose new nest sites near their own previously used sites. The scale of site fidelity varied, but generally males choose to renest within shoreline areas rather than specific or exact nest locations (94% within-year, 86% among-years). Iteroparous males also displayed no preference to nest in proximity to neighbouring males from previous colonies to suggest social fidelity. Contrary to expectation, manipulating males' reproductive success had no significant effect on the pattern or scale of male reproductive site fidelity.

Morbidity and mortality among a cohort of HIV-infected adults in a programme for community home-based care, in the Kilimanjaro Region of Tanzania (2003-2005)

Community home-based care (CHBC) plays an integral role in the care of HIV-infected patients living in resource-limited regions. A longitudinal cohort study has recently been conducted, in the Kilimanjaro Region of northern Tanzania, in order to identify the components of an effective CHBC programme. Structured questionnaires were administered to clients over two census rounds, one in October 2003-February 2004 and the other in January 2005-October 2005. In the second round, follow-up interviews were completed for 226 (87.9%) of the 257 clients included in the first round. The clients included in the first round had a median (range) age of 38 (20-66) years and 182 (75.2%) of them were female. Although only 27 (12.9%) of them were using antiretroviral therapy (ART) when first interviewed, 108 (44.6%) were taking trimethoprim-sulfamethoxazole (SXT) prophylaxis. By the time of the follow-up interviews, 102 (45.1%) of the clients included in the first round had died, giving a mortality of 51/100 person-years of observation. The primary cause of death for 87 (85.3%) of the clients who had died was respiratory and/or gastro-intestinal infection, and the most common contributory causes of death were malnutrition (81.4%) and anaemia (42.2%). On bivariable analysis, the following first-round conditions were found to be significantly associated with death by the second census round: weakness for >1 month [odds ratio (OR)=2.64; P=0.008]; oral thrush (OR=2.31; P=0.015); painful swallowing (OR=2.02; P=0.036); staying in bed for part of the day over most of the previous month (OR=1.94; P=0.017); fever for >1 month (OR=1.95; P=0.016); and severe bacterial infections (OR=1.80; P=0.036). The high mortality was associated with advanced, symptomatic HIV disease for which antiretroviral therapy was indicated. Clients who were in the advanced stages of HIV disease (as defined by the World Health Organization's criteria) in the first census round were significantly more likely to have died by the time of the second round than the other clients investigated (log-rank chi(2)=8.115; P=0.044). The high level of morbidity observed in this study, and the causes of mortality that were identified, emphasise the need for CHBC programmes to provide HIV-infected patients with improved access to basic resources such as SXT and isoniazid prophylaxis, clean water, oral rehydration therapy, and micronutrient supplementation, in addition to increased access to ART.

Low sensitivity of T-cell based detection of tuberculosis among HIV co-infected Tanzanian in-patients

OBJECTIVE

To evaluate the performance of QuantiFERON-TB GOLD (QFTG) in a resource-poor setting among patients with and without HIV infection.

DESIGN

Cross-sectional study.

SETTING

Two hospitals in Northern Tanzania.

SUBJECTS

Eighty three adult male and female inpatients.

INTERVENTION

All patients were screened for HIV infection and underwent tuberculin skin test (TST) and QFTG.

RESULTS

Eighty-three subjects were enrolled, and 29 (35%) of 83 were HIV-infected. QFTG yielded indeterminate results in 12 (22%; 95% CI 12%-34%) of 54 HIV-uninfected and 13 (45%; 95% CI 26%-64%) of 29 HIV-infected subjects (p = 0.0323). Among those with smear-positive pulmonary tuberculosis, TST was positive in 40 (100%; 95% CI 91%-100%) of 40 HIV-uninfected subjects compared with seven (54%; 95% CI 25%-81%) of 13 HIV-infected subjects (p < 0.0001), and QFTG was positive in 28 (70%; 95% CI 53%-83%) of 40 HIV-uninfected subjects compared with three (23%; 95% CI 5%-54%) of 13 HIV-infected subjects (p = 0.0029). Among medical inpatients at risk for latent tuberculosis infection, TST was positive in seven (50%) of 14 HIV-uninfected patients and three (19%) of 16 HIV-infected patients (p = 0.0701) and QFTG was positive among two (14%) of 14 HIV-uninfected patients and three (19%) of 16 HIV-infected patients (p = 0.7437).

CONCLUSIONS

The presence of HIV co-infection was associated with a significant reduction in sensitivity of both the TST (p < 0.0001) and QFTG (p = 0.0029) for the diagnosis of active M. tuberculosis infection. The high proportion of indeterminate QFTG and lack of sensitivity, particularly among HIV-infected patients, may limit its applicability in settings like Tanzania. Larger studies in resource-poor settings are required.

Microalbuminuria predicts overt proteinuria among patients with HIV infection

BACKGROUND

This study examines the association between microalbuminuria and the development of proteinuria among HIV-infected persons.

METHODS

A total of 948 subjects provided urine samples for albumin, protein and creatinine measurements semiannually. Microalbuminuria was defined as an albumin-to-creatinine ratio of >30 mg/g. Proteinuria was defined as a protein-to-creatinine ratio of > or =0.350 mg/mg. The progression from microalbuminuria to proteinuria was described.

RESULTS

At baseline, 69.4% of the subjects had no detectable proteinuria, 20.2% had microalbuminuria, and 10.4% had proteinuria. Subjects with microalbuminuria and proteinuria were more likely to be black (P=0.02), have lower CD4 cell counts (P=0.02 comparing subjects without abnormal urine protein excretion to subjects with microalbuminuria; P=0.0001 comparing subjects with microalbuminuria to subjects with proteinuria), and have a higher HIV RNA level (P=0.08 and 0.04, respectively). Among 658 subjects with normal urine protein, 82.7% continued to have no abnormality, 14.3% developed microalbuminuria, and 3.0% developed proteinuria. Subjects without baseline proteinuria (i.e. either normal protein excretion or microalbuminuria) who developed proteinuria were more likely to have microalbuminuria (P=0.001), a lower CD4 cell count (P=0.06), and a higher plasma HIV RNA (P=0.03) than those who did not progress to proteinuria. In multivariate analysis, only microalbuminuria remained associated with the development of proteinuria (odds ratio 2.9; 95% confidence interval 1.5, 5.5; P=0.001).

CONCLUSION

Microalbuminuria predicts the development of proteinuria among HIV-infected persons. Because proteinuria has been linked to poorer outcomes, strategies to affect microalbuminuria should be tested.

Missed opportunities for diagnosis of tuberculosis and human immunodeficiency virus co-infection in Moshi, Tanzania

SETTING

A community-based voluntary counseling and testing (VCT) center in Moshi, Tanzania.

OBJECTIVE

To compare rates of prior human immunodeficiency virus (HIV) testing among clients with and without previous tuberculosis (TB) treatment, and HIV seropositivity among those with and without current TB symptoms.

DESIGN

Cross-sectional study of consecutive clients presenting for initial testing; sociodemographic and clinical data were collected via a structured questionnaire. HIV status was compared among clients with or without three or more TB-related symptoms: weight loss, fever, cough, hemoptysis or night sweats.

RESULTS

Overall, 225 (3%) of 6583 VCT clients who responded to questions on previous TB treatment reported a history of TB, but only 34 (15%) reported previous HIV testing. This rate of HIV testing was not different from the rate among those clients without a history of TB (OR 0.77, P = 0.175). One hundred thirty-five (61%) clients with a history of TB were HIV-infected at VCT, compared with 17% of all clients. Of the total 6592 first-time testers who responded, 372 (6%) had at least three symptoms suggestive of TB at VCT. These symptoms were strongly associated with HIV seropositivity (OR 16.30, P < 0.001).

CONCLUSION

Missed opportunities for HIV diagnosis at the time of TB treatment appear frequent in this population, underscoring the need for integration of TB and HIV diagnostic services.

Sociodemographic and clinical characteristics of clients presenting for HIV voluntary counselling and testing in Moshi, Tanzania

HIV voluntary counselling and testing (VCT) reduces high-risk sexual behaviour. Factors associated with HIV infection in VCT clients have not been well characterized in northern Tanzania. We prospectively surveyed 813 VCT clients in Moshi, Tanzania. Clients were administered a questionnaire on sociodemographic characteristics, sexual behaviour, and health status. Blood was taken for rapid HIV antibody testing. Factors associated with HIV seropositivity were identified using multivariate logistic regression analysis. Of 813 clients, the seroprevalence was 16.7%. The strongest associations with seropositivity were reporting diarrhoea (odds ratio [OR] 10.4, 95% confidence interval [CI] 3.6-29.9), an ill sexual partner (OR 6.3, 95% CI 3.0-12.9), or being a woman (OR 3.5, 95% CI 2.0-6.3). In a separate regression, the number of symptoms also predicted HIV infection (OR 2.1, 95% CI 1.6-2.6). VCT clients who tested positive had more HIV-related symptoms suggesting presentation at a later stage of HIV infection.

HIV-associated morbidity, mortality and diagnostic testing opportunities among inpatients at a referral hospital in northern Tanzania

Hospitalized patients with HIV infection are among the most likely to benefit from the expanding availability of anti-retroviral therapy in sub-Saharan Africa. Between 1990 and 2000, 3667 people known to be HIV-infected were admitted to Kilimanjaro Christian Medical Centre (KCMC) in Moshi, northen Tanzania. The level of inpatient mortality among these patients varied from 15%-21%, and the proportion of the HIV-infected patients admitted who were female increased significantly, from 45% at the start of the study period to 52% at the end (P <0.001). When the medical records for 1683 of the HIV-infected patients who had been admitted between 1996 and 2001 were reviewed, the most prevalent diagnoses on admission were found to be pulmonary tuberculosis (21%), malaria (14%) and gastro-enteritis/diarrhoea (12%) among the adults, and non-tubercular pulmonary infection (21%), pulmonary tuberculosis (19%) and gastro-enteritis/diarrhoea (12%) among the children. The crude odds ratios (OR) for inpatient death were greatest for adults presenting with meningitis [OR=3.7; 95% confidence interval (CI)=2.1-6.7], septicaemia (OR=2.9; CI=1.2-7.3) or renal disease (OR=2.6; CI=1.2-5.7), and mortality was higher for men than for women (OR=1.4; CI=1.1-1.8). A single-day, point-prevalence survey in September 2001, among the KCMC's inpatients, identified HIV infection in 21% of those surveyed, many (44%) of the patients found positive being previously unaware of their infection. HIV infection remains a major cause of hospitalization and mortality in Moshi. A policy of routine testing would increase the number of HIV infections detected, allowing improvements in case management and in the prevention of infection.

Protease inhibitors are associated with a slowed progression of HIV-related renal diseases

AIMS

While angiotensin-con-verting enzyme inhibitors and zidovudine may improve the course of the most common HIV-related renal disease, HIV-associated nephropathy (HIVAN), the effect of anti-retroviral combination therapy on this and other HIV-related renal diseases has not been assessed. This study describes the clinical course of HIV-related renal diseases and the effect of protease inhibitors on their progression.

METHODS

This retrospective cohort study reviews the clinical course of 19 patients with a clinical or biopsy-proven diagnosis of HIVAN or other HIV-related renal diseases. Groups progressing and not progressing to ESRD were compared using longitudinal analyses to assess the association between creatinine clearance and clinical and therapeutic factors.

RESULTS

The cohort consisted of 16 African-Americans, 2 Caucasians and 1 Native American. Their modes of HIV infection were intravenous drug use (7), a history of men having sex with men (3) and heterosexual behavior (5). Patients were followed for a median of 16.6 months. Seven patients reached ESRD. Loss of creatinine clearance over time did not differ among genders, races, or patients with different modes of HIV infection. Longitudinal analyses demonstrated an association between protease inhibitors and prednisone and a slower decline in creatinine clearance in multivariable models (p = 0.04 and 0.003, respectively).

CONCLUSIONS

The epidemiology and clinical course of HIV-related renal diseases is more heterogeneous than previously described. This study suggests a benefit to the use of protease inhibitors and prednisone on the progression of these nephropathies.

Addressing the challenges of adherence

Adherence to antiretroviral therapy is a crucial determinant of treatment success. Studies have unequivocally demonstrated the close association between adherence and plasma HIV RNA levels, CD4 cell counts, and mortality in patients with HIV infection and disease. Adherence levels of > or =95% are required to maintain virologic suppression. However, actual adherence rates are often far lower; most studies show that 40% to 60% of patients are <90% adherent. Adherence also tends to decrease over time. Patients offer a range of reasons for nonadherence, but the most frequently cited one is simply that they forget; other reasons include being away from home, being busy, or experiencing a change in daily routine. Additional barriers to adherence include psychiatric disorders, such as depression or substance use, uncertainty about the effectiveness of treatment and the consequences of poor adherence, regimen complexity, and treatment side effects. Several strategies can be employed in the effort to support patients' adherence, and all members of the multidisciplinary team should ideally employ these strategies in combination. Efforts should be made to educate and motivate patients, simplify treatment regimens and tailor them to individual lifestyles, prepare for and manage side effects, and address the concrete issues that may be a barrier to adherence. Recruiting an adherence monitor, providing memory aids to medication taking, and anticipating course corrections can also help patients achieve the adherence rates needed for successful treatment of HIV infection and disease.

Thymopoiesis in HIV-infected adults after highly active antiretroviral therapy

The thymus of HIV-seropositive patients can enlarge as CD4+ T cell counts increase on highly active anti-retroviral therapy (HAART). This may indicate development of new T cells or represent mature peripheral T cells recirculating to the thymus. To define the etiology of the enlargement, the thymuses of two HIV-infected individuals on HAART were biopsied. For more than 3 years before initiation of HAART, both patients (38 and 41 years of age) had documented CD4+ T lymphopenia. Peripheral blood samples were obtained to assess circulating CD4+ CD45RA+ CD62L+ T cells, which were thought to have recently developed in the thymus. Peripheral blood T cells from both patients and thymocytes from the second patient were also tested for levels of DNA episomes formed during T cell receptor gene rearrangement (T cell receptor rearrangement excision circles, TRECs). With HAART, peripheral blood CD4+ T cell counts increased from approximately 60/mm(3) to 552/mm(3) and 750/mm(3) for patients 1 and 2, respectively. Thymic biopsies from both patients showed normal thymus histology with active thymopoiesis. Percentages of peripheral blood CD4+ CD45RA+ CD62L+ T cells and quantitation of T cell TRECs also reflected active thymopoiesis in both patients. Thus, in these two HIV-seropositive adults examined after initiation of HAART, thymic enlargement represented active thymopoiesis. Thymopoiesis in adult AIDS patients may contribute to immune reconstitution even after prolonged CD4+ T lymphopenia.

Structured antiretroviral treatment interruptions in chronically HIV-1-infected subjects

The risks and benefits of structured treatment interruption (STI) in HIV-1-infected subjects are not fully understood. A pilot study was performed to compare STI with continuous highly active antiretroviral therapy (HAART) in chronic HIV-1-infected subjects with HIV-1 plasma RNA levels (VL) <400 copies per ml and CD4(+) T cells >400 per microl. CD4(+) T cells, VL, HIV-1-specific neutralizing antibodies, and IFN-gamma-producing HIV-1-specific CD8(+) and CD4(+) T cells were measured in all subjects. STIs of 1-month duration separated by 1 month of HAART, before a final 3-month STI, resulted in augmented CD8(+) T cell responses in all eight STI subjects (P = 0.003), maintained while on HAART up to 22 weeks after STI, and augmented neutralization titers to autologous HIV-1 isolate in one of eight subjects. However, significant decline of CD4(+) T cell count from pre-STI level, and VL rebound to pre-HAART baseline, occurred during STI (P = 0.001 and 0.34, respectively). CD4(+) T cell counts were regained on return to HAART. Control subjects (n = 4) maintained VL <400 copies per ml and stable CD4(+) T cell counts, and showed no enhancement of antiviral CD8(+) T cell responses. Despite increases in antiviral immunity, no control of VL was observed. Future studies of STI should proceed with caution.

Primary care for patients infected with human immunodeficiency virus: a randomized controlled trial

OBJECTIVE

To measure the impact of a teaching intervention and to compare process and outcomes of care for HIV-infected patients randomly assigned to a general medicine clinic (GMC) or an infectious disease clinic (IDC) for primary care.

DESIGN

Prospective, randomized, controlled trial.

SETTING

University hospital in Durham, NC.

PATIENTS

Two hundred fourteen consecutive HIV-infected patients presenting for primary care.

INTERVENTION

Physicians at the GMC received HIV-related training and evidence-based practice guidelines.

MEASUREMENTS

Utilization of services, health-related quality of life, preventive and screening measures, and antiretroviral use for one year.

RESULTS

At baseline GMC patients were more likely to be African American (85% vs 71%; P =.03) and had lower baseline CD4+ cell counts than IDC patients (262 +/- 269 vs 329 +/- 275; P =.05). A similar and high proportion of patients in both groups received appropriate preventive care services including Pneumocystis carinii pneumonia (PCP) prophylaxis, pneumococcal vaccination, and antiretroviral therapy. Screening for TB was more frequent in GMC (89% vs 68%; P =.001). In the year following randomization, GMC patients made more visits to the emergency department than IDC patients (1.6 +/- 3.0 vs 0.7 +/- 1.5; P =.05). Hospital use was higher for GMC patients with average length of stay 7.8 +/- 6.3 days compared to 5.7 +/- 3.8 days for IDC patients (P =.01). In analyses, which adjust for potential baseline imbalances, these differences remained.

CONCLUSIONS

Targeted education in GMC achieved similar provision of primary care for GMC patients, yet use of health care services was higher for this group. The delivery of adequate primary care is necessary but not sufficient to produce changes in health care utilization.

Overview of the effectiveness of triple combination therapy in antiretroviral-naive HIV-1 infected adults

AIM

To estimate the effectiveness of triple combination therapy in antiretroviral-naive adults.

METHODS

A systematic overview of results from clinical trials involving triple combination therapy with dual nucleoside reverse transcriptase inhibitors (NRTI) and: a protease inhibitor (PI triple); a non-nucleoside reverse transcriptase inhibitor (NNRTI triple); or a third NRTI (triple NUC). Data from 23 clinical trials involving 31 independent treatment groups, 19 unique antiretroviral regimens, and 3257 enrolled patients were included in this study.

RESULTS

Median log(10) baseline plasma HIV RNA and CD4 cell count over all trials averaged 4.69 (49,329 copies/ml) and 375 x 10(6) cells/l, respectively. The overall estimated percentage of patients with plasma HIV RNA < or = 400 copies/ml at 24 weeks was 64% [95% confidence interval (CI), 60 to 67%]. The percentages of patients with plasma HIV RNA < or = 50 copies/ml at 48 weeks by drug class were: PI triple, 46% (95% CI, 41 to 52%); NNRTI triple, 51% (95% CI, 43 to 59%); triple NUC, 45% (95% CI, 36 to 54%). The CD4 cell count increase over all trials at 24 and 48 weeks averaged +123 x 10(6) cells/l (95% CI, 111 x 10(6) to 135 x 10(6) cells/l) and +160 x 10(6) cells/l (95% CI, 146 x 10(6) to 175 x 10(6) cells/l), respectively and did not differ between drug classes. In multivariable regression analysis, neither baseline plasma HIV RNA level and CD4 cell count nor treatment regimen predicted plasma HIV RNA < or = 50 copies/ml at week 48. However, pill count was significantly negatively associated with plasma HIV RNA < or = 50 copies/ml at week 48 (P = 0.0085).

CONCLUSIONS

The results suggest that three drug regimens containing two NRTI with a PI, a NNRTI, or a third NRTI may provide comparable activity, and practical issues such as daily pill burden should be considered when choosing a treatment regimen.

Immune function in healthy inner-city children

The importance of investigating immunity in healthy children has been underscored in the last few years by studies of the immune pathology of childhood illnesses, including human immunodeficiency virus. This study reports both ennumerative and functional immune measures in healthy inner city children. A total of 152 of 207 children studied were completely heathy at the time of venipuncture and were included in this study. Laboratory immune batteries were completed (or begun) the same day as venipuncture. Relationships between age, gender, ethnicity, and immunity were then analyzed. We found that gender predicted both the absolute number and the percentage of T cells and helper cells and the percentage of natural killer cells. Total leukocyte counts and percentages of lymphocytes and granulocytes were related to ethnicity, as was the response to mitogen stimulation (concanavalin A and pokeweed mitogen) and phagocytic ability. In conclusion, age, gender, and ethnicity factors were found to contribute to differences in various immune measures in children and require further investigation.

Immunologic profile of human immunodeficiency virus-infected patients during viral remission and relapse on antiretroviral therapy

A dissociation between plasma human immunodeficiency virus (HIV) RNA levels and CD4(+) cell counts has been reported in patients experiencing viral relapse while receiving antiretroviral therapy. This study compared patients with stable CD4(+) lymphocytes during viral relapse while receiving treatment with patients who had sustained virus suppression. Plasma HIV RNA levels, lymphocyte immunophenotyping, and T cell receptor excision circle (TREC) levels were measured. Naive CD4(+) lymphocyte phenotype and TREC levels were not significantly different in patients with virus suppression or in those who had relapsed. However, CD8(+) lymphocyte activation, including the number and percentage of activated cells and CD38 antibody-binding capacity, was significantly elevated during viral relapse, compared with that in suppressed patients. By multivariable regression analyses, CD8(+) and CD4(+) lymphocyte activation were associated significantly with increasing plasma HIV RNA levels.

Influence of neurological level on immune function following spinal cord injury: a review

Due to the high incidence of lifelong infections in persons with spinal cord injury (SCI), the authors examined level of injury-related immune characteristics in a cohort of subjects with chronic SCI. Since the sympathetic nervous system and the endocrine system are known to be modulators of immune function, one possible explanation for heightened incidence of infections includes dysregulation of sympathetic outflow tracts in individuals with tetraplegia or high paraplegia. Natural killer cell cytotoxicity (NKCC) and bactericidal function of circulating neutrophils were assayed in a group of 10 individuals with chronic complete cervical SCI, a group of 8 individuals with paraplegia with injuries below the main sympathetic outflow (T-10 and below) and a group of 18 age- and sex-matched controls. In addition, a psychiatric assessment of depression was performed as well as assays of pituitary and adrenal functions. Analyses revealed no significant differences in immune function between all subjects with SCI combined and their matched controls. Further analyses stratifying based on presence or absence of sympathetic dysregulation revealed significantly impaired phagocytic ability and a trend toward reduced NKCC in the group with tetraplegia compared with their controls. Hormonal assays showed that dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DS) were higher in individuals with tetraplegia than controls, but no such differences were observed in individuals with paraplegia compared with their controls. The results of this study suggest that individuals sustaining complete cervical SCI experience alterations in immune function, while those with lesions at or below T-10 do not. These findings of level of injury related immune alteration could not be explained by mood differences. This paper is a review of previously published work and the authors' current thinking regarding increased acquisition of infections in this population.

The isolation of FOS-1, a gene encoding a putative two-component histidine kinase from Aspergillus fumigatus

In fungi, two-component histidine kinases are involved in response mechanisms to extracellular changes in osmolarity, resistance to dicarboximide fungicides, and cell-wall assembly. In the human opportunistic fungus, Candida albicans, each of the three histidine kinases plays a role in virulence. Here, we identify, for the first time, a gene, FOS-1, from the human pathogenic fungus Aspergillus fumigatus that predicts a protein with homology to two-component histidine kinases. The predicted FOS-1 protein is highly homologous to bacterial and other fungal histidine kinases in several functional domains, but is divergent at the amino- and carboxy-termini. A mutant lacking the FOS-1 locus, DeltaFOS-1, did not exhibit a detectable defect in either hyphal growth or morphology when grown on solid or liquid medium. However, in liquid medium, conidiophore development of the DeltaFOS-1 mutant was delayed. Compared to wild type, the DeltaFOS-1 strain was neither osmotically sensitive nor sensitive or resistant to a number of nondicarboximide antifungal drugs, but was highly resistant to dicarboximide fungicides and resistant to novozym 234, suggesting that FOS-1p may play a role in the regulation of cell-wall assembly.

Effect of highly active antiretroviral therapy and thymic transplantation on immunoreconstitution in HIV infection

The purpose of this study was to determine whether thymic transplantation in addition to highly active antiretroviral therapy (HAART) will restore T cell function in HIV infection. Eight treatment-naive HIV-infected patients with CD4+ T cell counts of 200-500/mm3 were randomized into thymic transplantation and control arms. All patients received HAART (zidovudine, lamivudine, and ritonavir) for 6 weeks prior to transplantation. Thymic transplantation was done without immunosuppression, using postnatal HLA-unmatched cultured allogeneic thymus tissue. Patients were immunized every 6 months with the neoantigen keyhole limpet hemocyanin (KLH) and the recall antigen tetanus toxoid (TT). T cell phenotype and function and T cell receptor rearrangement excision circles (TRECs) were assessed. Thymic allografts were biopsied at 2 months. Six HIV-infected patients completed the study. Four patients received cultured allogeneic postnatal thymic grafts, two others were controls. CD4+ T cell counts increased and T cell-proliferative responses to Candida antigen and TT normalized in all patients. Proliferative responses to KLH developed in three of four transplant recipients and one of two controls. Patients responding to KLH after secondary immunization had greater TREC increases compared with the patients who did not respond. All thymic allografts were rejected within 2 months. In summary, four of six patients developed T cell-proliferative responses to the neoantigen KLH over the first 2 years of HAART. The transplanted thymus tissue, however, was rejected. There was no clear difference in restoration of T cell function in the transplant recipients compared with the controls. Increases in TRECs after initiation of HAART may correlate with improved immune function.

Effect of molecular structure on the performance of triarylmethane dyes as therapeutic agents for photochemical purging of autologous bone marrow grafts from residual tumor cells

Extensively conjugated cationic molecules with appropriate structural features naturally accumulate into the mitochondria of living cells, a phenomenon typically more prominent in tumor than in normal cells. Because a variety of tumor cells also retain pertinent cationic structures for longer periods of time compared with normal cells, mitochondrial targeting has been proposed as a selective therapeutic strategy of relevance for both chemotherapy and photochemotherapy of neoplastic diseases. Here we report that the triarylmethane dye crystal violet stains cell mitochondria with efficiency and selectivity, and is a promising candidate for photochemotherapy applications. Crystal violet exhibits pronounced phototoxicity toward L1210 leukemia cells but comparatively small toxic effects toward normal hematopoietic cells (murine granulocyte-macrophage progenitors, CFU-GM). On the basis of a comparative examination of chemical, photochemical, and phototoxic properties of crystal violet and other triarylmethane dyes, we have identified interdependencies between molecular structure, and selective phototoxicity toward tumor cells. These structure-activity relationships represent useful guidelines for the development of novel purging protocols to promote selective elimination of residual tumor cells from autologous bone marrow grafts with minimum toxicity to normal hematopoietic stem cells.

Meningococcemia in a patient coinfected with hepatitis C virus and HIV

We describe the first reported case of meningococcemia in a patient coinfected with hepatitis C virus and HIV. Hypocomplementemia secondary to hepatic dysfunction may have enhanced the patient's susceptibility to meningococcal infection.

Population pharmacokinetics of lamivudine in adult human immunodeficiency virus-infected patients enrolled in two phase III clinical trials

Lamivudine population pharmacokinetics were investigated by using nonlinear mixed-effect modelling (NONMEM) analysis of data from 394 human immunodeficiency virus (HIV)-infected patients treated with lamivudine (150 to 300 mg every 12 h) in two large, phase III clinical efficacy-safety trials, NUCA3001 and NUCA3002. Analyses of 1,477 serum lamivudine concentration determinations showed that population estimates for lamivudine oral clearance (CL/F; 25.1 liters/h) and volume of distribution (V/F; 128 liters) were similar to values previously reported for HIV-infected patients in phase I pharmacokinetic studies. Lamivudine CL/F was significantly influenced by the covariates creatinine clearance and weight and not affected by age, Centers for Disease Control and Prevention (CDC) classification, CD4(+) cell count, HIV type 1 (HIV-1) RNA PCR, or gender and race when CL/F was corrected for differences in patient weight. The population estimate for lamivudine V/F was not significantly influenced by the covariates gender, race, age, weight, renal function, HIV-1 RNA PCR, or CDC classification and CD4(+) cell count when creatinine clearance was included with CL/F in the model. Lamivudine disposition was significantly influenced by renal function. However, as only three patients had an estimated creatinine clearance of <60 ml/min, dosage adjustments for patients with impaired renal function should not be determined based on the population parameters derived in this analysis.

Strategies of antiretroviral therapy in adults

Recent progress in antiretroviral treatment has led to dramatic improvements in HIV-related morbidity and mortality. These improvements have been fostered by advances in our understanding of HIV-related pathogenesis, the use of plasma HIV RNA levels to monitor patients, and the availability of 13 licensed antiretroviral drugs. Numerous drug combinations, especially those containing three or more agents, can suppress plasma HIV RNA levels below the lower limit of detection in the majority of treated patients. Urologists should be familiar with the limitations of this therapeutic response: patient adherence, drug resistance, a residual burden of chronically infected cells which are refractory to treatment, an unknown impact on HIV in genital secretions, and potential transmissibility through sexual contact.

Effect of self-association and protein binding on the photochemical reactivity of triarylmethanes. Implications of noncovalent interactions on the competition between photosensitization mechanisms type I and type II

We have explored the photochemical behavior of cationic triarylmethane dye monomers and dimers free in solution and noncovalently bound to bovine serum albumin (BSA) and examined how self-association and the formation of host-guest complexes involving biopolymers and photosensitizers affect the competition between the photosensitization type I and type II mechanisms. Our results have clearly indicated that tri-para-substituted triarylmethane dyes bind efficiently to albumin as monomers and dimers and, interestingly, that the formation of dye aggregates in aqueous solutions is actually assisted by the protein. Protein-assisted dye aggregation takes place under conditions of high biopolymer loading (high [dye]/[protein] ratios), as attested by the appearance of a hypsochromically shifted absorption band (H-band) that overlaps with the spectral shoulder of the respective dye monomer. As predicted by the molecular exciton theory, the intersystem crossing efficiency in H-type dimers is expected to be higher than in the respective dye monomers, and photoinduced electron transfer events are intrinsically favored in dye aggregates as a result of the physical contact between donor and acceptor. We have found that when triarylmethanes are noncovalently bound to BSA their photoreactivity undergoes a remarkable enhancement, and that the photooxidation mechanism type I is particularly favored in the macromolecular environment. A comparative examination of the behavior of triarylmethane dyes with that of methylene blue have shown that in the case of methylene blue the binding phenomenon also favor the type I mechanism.

Systemic health consequences of alloplastic implants of the TMJ: a pilot study

The aim of this study was to examine the relation between alloplastic temporomandibular joint (TMJ) implants and immune-associated systemic health problems. The authors compared 14 patients who received alloplastic TMJ implants with 31 TMJ patients who had never received surgery on the self-reported occurrence of symptoms and systemic disorders that are associated with problems of immunomodulation. Those with alloplastic jaw implants reported similar or lower rates of surveyed physical disorders than nonsurgical TMJ participants. When the rates were summed across symptom categories and physical disorders, implant participants had significantly fewer symptoms and disorders than nonsurgical participants (P < 0.01). This first report on systemic health problems in alloplastic TMJ implant patients found no evidence of elevated rates of systemic disorders that are associated with problems of immunomodulation.

Adrenal and pituitary hormone patterns after spinal cord injury

Current evidence indicates that the neuroendocrine system is the highest regulator of immune/inflammatory reactions. We hypothesized that immune alterations, which were related to the level of injury, found in a cohort of spinal cord-injured subjects may be influenced by altered hormonal patterns postinjury. Therefore, we investigated aspects of both pituitary and adrenal function in the same cohort of spinal cord-injured subjects. We found significant elevations in both cortisol and dehydroepiandrosterone sulfate in chronic spinal cord-injured survivors compared with their able-bodied age- and gender-matched controls. Levels of dehydroepiandrosterone, adrenocorticotropin, and prolactin were not different in spinal cord-injured subjects overall compared with their controls. Both dehydroepiandrosterone sulfate and dehydroepiandrosterone were higher in tetraplegics compared with their controls, but we found no such differences in paraplegics compared with their controls. When the two groups of spinal cord-injured subjects were compared with each other, we also found differences between these two subject groups in dehydroepiandrosterone sulfate and dehydroepiandrosterone (higher in the tetraplegics compared with paraplegics). We found no differences between either group of spinal cord-injured subjects and their controls for adrenocorticotropin, prolactin, or cortisol. These data suggest that some hormonal differences between subjects and their controls may be further related to the level of injury (specifically dehydroepiandrosterone and dehydroepiandrosterone). Finally, we investigated correlations within subjects for the above hormones. Dehydroepiandrosterone sulfate and prolactin were highly correlated (the higher the dehydroepiandrosterone sulfate, the higher the prolactin) but only in the tetraplegic subjects.

Self-reported systemic, immune-mediated disorders in patients with and without proplast-teflon implants of the temporomandibular joint

PURPOSE

This study investigates the self-reported immune-related health status of patients exposed to Proplast-Teflon (P/T) temporomandibular joint (TMJ) implants, comparing their health status with a group of patients who were not exposed to any alloplastic TMJ implants. It also compares those whose implants were removed with those in whom they were retained.

PATIENTS AND METHODS

Patients seen in a single oral and maxillofacial surgical practice completed a detailed self-report questionnaire about physical symptoms and disorders. Sixty-four had received P/T implants, and 22 were unexposed to any TMJ alloplastic implant. Of the P/T-exposed group, 44 had removed and 20 had retained implants.

RESULTS

In general, P/T-exposed patients did not differ from unexposed patients in rates of reported immune-mediated and somatization-related conditions, allergies, or symptoms of environmental sensitivity. However, patients with removed P/T implants reported significantly more problems in all categories of conditions than those with retained P/T implants. This difference was no longer statistically significant after controlling for pain severity and sex.

CONCLUSIONS

Although P/T-exposed patients do not report more systemic health conditions than similar patients who were unexposed to alloplastic jaw implants, those with removed implants report more conditions and are more likely to be seen in clinical practice. This may lead to a bias in the general perception regarding the systemic health status of P/T-exposed patients. In addition, effects may be secondary to high levels of pain and dysfunction among patients with removed implants, rather than implant exposure itself. Future prospective research is needed to identify factors associated with implant failure.

Analysis of the adult thymus in reconstitution of T lymphocytes in HIV-1 infection

A key question in understanding the status of the immune system in HIV-1 infection is whether the adult thymus contributes to reconstitution of peripheral T lymphocytes. We analyzed the thymus in adult patients who died of HIV-1 infection. In addition, we studied the clinical course of HIV-1 infection in three patients thymectomized for myasthenia gravis and determined the effect of antiretroviral therapy on CD4(+) T cells. We found that five of seven patients had thymus tissue at autopsy and that all thymuses identified had inflammatory infiltrates surrounding lymphodepleted thymic epithelium. Two of seven patients also had areas of thymopoiesis; one of these patients had peripheral blood CD4(+) T-cell levels of <50/mm3 for 51 months prior to death. Of three thymectomized patients, one rapidly progressed to AIDS, one progressed to AIDS over seven years (normal progressor), whereas the third remains asymptomatic at least seven years after seroconversion. Both latter patients had rises in peripheral blood CD4(+) T cells after antiretroviral therapy. Most patients who died of complications of HIV-1 infection did not have functional thymus tissue, and when present, thymopoiesis did not prevent prolonged lymphopenia. Thymectomy before HIV-1 infection did not preclude either peripheral CD4(+) T-cell rises or clinical responses after antiretroviral therapy.

Depression and immunity: clinical factors and therapeutic course

While many reports describe associations between depressive disorders and altered immunity, findings have not been fully consistent. Diagnostic subtype, demographic factors such as age and gender, medical characteristics, and the immune measures selected for assessment may have contributed to the heterogeneous findings. In a study of 21 medically healthy young adults with major depression, we found, consistent with previous reports, evidence of increased lymphocyte activation to mitogen challenge and decreased natural killer (NK) cell numbers and function during acute depression. Fifteen subjects were followed longitudinally. T, CD4+, CD29+, and CD45RA+ lymphocytes and T-cell mitogen responses decreased significantly (P<0.05) during 6 weeks of pharmacotherapy and concurrent clinical improvement. There was no change in NK activity or CD56+ cells. The longitudinal effects appeared unrelated to tricyclic antidepressant levels. Changes in the immune system with short-term clinical improvement in depressed patients are not uniform providing further evidence that several mechanisms are involved in the altered immunity associated with clinical depression.

Primary care of HIV infection

Four cases illustrate some of the issues involved in treating HIV-infected patients in a primary care setting. Primary care physicians are hard-pressed to achieve the same results as infectious disease specialists, yet are increasingly responsible for performing the initial tests, choosing the therapeutic regimen, ensuring the patient's compliance with the regimen, and monitoring the results.

Variability in repeated consecutive measurements of plasma human immunodeficiency virus RNA in persons receiving stable nucleoside reverse transcriptase inhibitor therapy or no treatment

Plasma human immunodeficiency virus (HIV) RNA levels correlate closely with clinical prognosis in both treated and untreated HIV-infected persons and are widely used to guide clinical practice and as a primary end point in clinical trials. Thus, variability in these measurements may significantly affect their interpretation in clinical practice and research. The variability in consecutive measurements of plasma HIV RNA levels was studied in 387 subjects receiving either stable nucleoside reverse transcriptase inhibitor therapy or no treatment. The Pearson's correlation coefficient between baseline measures 2 weeks apart was 0.92. The mean SD in consecutive measurements 1 month apart was 0.31 log10 copies/mL with a 95% tolerance limit of 0.7 log10 copies/mL (5-fold). Two-thirds of the total variance in consecutive measures 1 month apart was due to biologic fluctuation; one-third was due to assay variance. The biologic variance increased proportionately with the number of weeks between assessments. Clinicians and investigators should be aware of the magnitude of variability in viral RNA levels in the HIV-infected population.

Coadministration of zidovudine and interleukin-2 increases absolute CD4 cells in subjects with Walter Reed stage 2 human immunodeficiency virus infection: results of ACTG protocol 042

Interleukin-2 (IL-2) can increase numbers of absolute CD4 cells in persons infected with the human immunodeficiency virus who are receiving antiretroviral therapy. Twenty-five subjects with > 400/mm3 absolute CD4 cells received zidovudine and low-dose intravenous or subcutaneous IL-2 (< or = 10(6) U/m2). Absolute CD4 cells increased significantly during IL-2 treatment, and 56% of the subjects achieved a maximal increase of > or = 500 cells/mm3. A dose-response relationship favored increasing IL-2 doses, and subcutaneous delivery offered greater increases than intravenous administration. Fifteen subjects had persistent increases of > or = 100 cells/mm3 6 weeks after IL-2 was discontinued. No changes occurred in delayed-type hypersensitivity or helper T cell responses to recall antigens. Cell-mediated cytotoxicities increased against Daudi cells. IL-2 was well tolerated and only 1 subject required dose reduction. Relatively low-dose IL-2 delivered by subcutaneous or intravenous routes may provide an important complement to antiretroviral therapy to increase absolute CD4 cells with the potential for less toxicity than with higher IL-2 doses.

Lymphokine-activated killer (LAK) cell anti-HIV-1 ADCC reactivity: a potential strategy for reduction of virus-infected cellular reservoirs

Lymphocytes from HIV-1-seropositive and -seronegative individuals were examined to determine whether HIV-1 infection interfered with the ability to generate a lymphokine-activated killer (LAK) cell response. Following a 3-day ex vivo incubation in the presence of 1000 U/ml of recombinant interleukin-2, lymphocytes from seropositive individuals exhibited a LAK cell response which was equivalent to or greater than that of seronegative controls as measured against Daudi cell targets. LAK cells from seropositive and seronegative donors showed no specific cytolytic activity against gp120-coated or HIV-1-infected targets. However, in the presence of patient sera, significant levels of virus-specific LAK cell-mediated antibody-dependent cellular cytotoxicity (ADCC) were observed. The level of this specific LAK cell-mediated ADCC was greater than that mediated under similar conditions by freshly isolated peripheral blood mononuclear cells. The greatest improvement in ADCC over baseline activity was seen with lymphocytes from AIDS patients after the 3-day ex vivo activation, suggesting that this patient population might benefit the most from adaptive LAK cell therapy.

Safety and immunogenicity of an HLA-based HIV envelope polyvalent synthetic peptide immunogen. DATRI 010 Study Group. Division of AIDS Treatment Research Initiative

OBJECTIVE

To evaluate the safety and immunogenicity of a polyvalent (PV) HIV envelope synthetic peptide immunogen, C4-V3. The immunogen comprised four peptides containing T-helper epitopes from the fourth constant region (C4) of gp120 of HIV-1MN, and T-helper, cytotoxic T-lymphocyte HLA-B7-restricted, and B-cell neutralizing epitopes from the gp120 third variable region (V3) of four clade B HIV-1 isolates, HIV-1MN, HIV-1RF, HIV-1EV91, and HIV-1Can0A.

DESIGN

A pilot, Phase I controlled trial [Division of AIDS Treatment Research Initiative (DATRI) 010] conducted at a single center.

METHODS

Ten HIV-infected, HLA-B7-positive patients with CD4 cells > 500 x 10(6)/l were enrolled. Eight patients received the C4-V3 PV immunogen emulsified in incomplete Freund's adjuvant in five intramuscular injections over 24 weeks, and two controls received incomplete Freund's adjuvant alone. All subjects were followed for 52 weeks.

RESULTS

Four out of eight C4-V3 PV recipients generated at least fourfold rise in serum antibody titers to at least three immunogen peptides in contrast to none of the control subjects. Four out of eight C4-V3 PV recipients and none of the controls had an at least fourfold rise in neutralizing antibodies to either HIV-1MN, HIV-1RF, or HIV-1(4489-5) laboratory-adapted HIV isolates. 3H-Thymidine incorporation assays of peripheral blood mononuclear cells increased at least fivefold over the baseline stimulation index to at least one of the immunogen peptides in two consecutive post-immunization timepoints in five out of eight C4-V3 PV recipients versus none of the controls. CD4 cell counts and plasma HIV RNA levels did not change in patients who received either C4-V3 PV or adjuvant alone. Adverse events consisted primarily of grade 1 injection site reactions in six subjects (four C4-V3 recipients, two controls).

CONCLUSIONS

C4-V3 PV synthetic peptides demonstrated both immunogenicity and safety in HIV-infected patients.

A placebo-controlled trial of ranitidine in patients with early human immunodeficiency virus infection

Previous uncontrolled reports have suggested that H2-antagonists may possess immunomodulatory activity in human immunodeficiency virus (HIV)-infected patients. Such trials reported improvements in HIV-related symptoms, increased absolute CD4 cell numbers, and improvements in other measures of host immunity. The present trial was a randomized, placebo-controlled, double-blind trial of ranitidine 300 mg (orally twice daily) in subjects with early HIV infection (absolute CD4 cells, 400-700/mm3). Eighty-one subjects entered the trial and 73 completed 16 weeks on study medications. There were no significant differences in the time-weighted average change from baseline between the 2 treatment groups in absolute CD4 cell number, plasma HIV RNA level, or most other surrogate markers of HIV infection. Serum beta2-microglobulin levels were significantly lower in placebo than ranitidine recipients. Ranitidine should not be recommended for the treatment of HIV-infected patients unless it is used for established indications.

Immune function in healthy adolescents

In the present study, we examine immunological functioning in normal healthy African-American and Latino/Latina adolescents recruited from an inner-city high school and an inner-city clinic. A battery of tests was performed with enumerative and functional measures which encompassed both innate and adaptive immunity. We found immune differences related to age, gender, and race on both the enumerative and the functional immune measures. This data expands the available body of information concerning normal immunity in healthy adolescents.

Itraconazole maintenance treatment for histoplasmosis in AIDS: a prospective, multicenter trial

PURPOSE

To study the efficacy and safety of maintenance treatment with itraconazole for disseminated histoplasmosis in patients with AIDS.

PATIENTS AND METHODS

This was a prospective, multicenter, open-label study conducted at university-based hospitals participating in the AIDS Clinical Trial Group (ACTG). Forty-six AIDS patients with mild to moderate disseminated histoplasmosis who had successfully completed 12 weeks of induction treatment with itraconazole were treated with itraconazole, 200 mg once daily (42 patients) or 400 mg once daily (4 patients). Patients were followed at monthly intervals with clinical and laboratory assessment for relapse or toxicity. Primary outcome measures were relapse of histoplasmosis and survival. Secondary outcome measures included drug-limiting toxicity and changes in serum and urine Histoplasma polysaccharide antigen (HPA) levels.

RESULTS

Two patients relapsed during a median follow-up period of 87 weeks. The 1-year relapse-free rate was estimated to be 95.3% (95% CI, 85.3%-99.7%). One relapse may have been related to poor adherence to treatment and the second to concurrent administration of rifampin. From the start of maintenance treatment, the estimated 1-year survival rate was 73.0% (95% CI, 67.5%-77.9%). Five patients discontinued treatment because of suspected drug toxicity, three of whom had possible or probable hepatotoxicity. Median serum and urine HPA levels declined significantly during treatment. The only patient in whom antigen levels rose >2 U developed clinical relapse 1 week later; antigen levels were unavailable in the other relapsing patient.

CONCLUSIONS

Itraconazole, 200 mg daily, is effective in preventing relapse of disseminated histoplasmosis in patients with AIDS. It is generally well tolerated, but clinicians should be alert for drug interactions and possible hepatotoxicity.

Central nervous system pneumocystosis in a patient with AIDS

Extrapulmonary involvement with Pneumocystis carinii has been described in 0.5%-2.5% of persons with AIDS. One hundred nine patients with AIDS and confirmed extrapulmonary pneumocystosis were identified, and seven of these patients (including our patients) had central nervous system (CNS) pneumocystosis. Of these seven patients, six had prior AIDS-related complications, and three had previous P. carinii pneumonia. Six patients had CNS symptoms, one of whom underwent a focal neurological examination. No cases were diagnosed before death. The involved sites were the cerebral cortex (2 patients), meninges (2), pituitary gland (1), putamen (1), and nonspecified locations (3). In two patients, organisms were seen around blood vessels, and in five patients there was concurrent neuropathology. In summary, CNS involvement with P. carinii usually occurs as a late complication of AIDS and probably represents hematogenous dissemination.

Impaired phagocytosis of Staphylococcus aureus in complete tetraplegics

Accumulating evidence implicates the sympathetic nervous system as a modulator of immune function. Immune alteration has been observed in survivors of cervical level spinal cord injury, possibly because of dysregulation of the sympathetic outflow tracts. The majority of immune studies in the spinal cord-injured population have focused on lymphocytes. Because of the high incidence of infections in this population, we hypothesized that the immune alteration would extend to the cells of the myeloid lineage. This hypothesis was tested by analyzing the phagocytic and bactericidal function of circulating neutrophils in response to Staphylococcus aureus. A group of ten individuals with complete cervical spinal cord injury, a group of eight paraplegics with injuries below the majority of sympathetic outflow (T-10 and below), and age- and gender-matched controls for each subject were studied. In addition, a psychiatric screening for depression was completed by all subjects and controls. Paired t test revealed significantly impaired phagocytic ability in the tetraplegic group compared with their controls. The paraplegic group did not demonstrate these findings. Our results suggest that individuals who have sustained complete cervical spinal cord injury have alteration in immune function compared with neurologically intact controls, whereas those with lesions at or below T-10 do not. This in vitro finding may be related to infection after cervical spinal cord injury. The mechanism may involve dysregulation of the sympathetic arm of the autonomic nervous system.

Phagocytosis and killing of Staphylococcus aureus: effects of stress and depression in children

While a large body of literature depicting relationships between depression or stress and immunity exists, few such studies have dealt with children, and none investigated myeloid cell-derived immunity. We investigated both phagocytosis and bactericidal activity against Staphylococcus aureus in children with major depressive disorder (MDD). We found that both MDD and stress influence the bactericidal but not the phagocytic activity of polymorphonuclear leukocytes. The data support the existence of psychobiologic effects in children and suggest possible mechanisms by which depression and stress may affect health.

Safety and pharmacokinetics of 5-chloro-2',3'-dideoxy-3'-fluorouridine (935U83) following oral administration of escalating single doses in human immunodeficiency virus-infected adults

5-Chloro-2',3'-dideoxy-3'-fluorouridine (935U83) is a nucleoside analog reverse transcriptase inhibitor that has demonstrated selective anti-human immunodeficiency virus (HIV) activity in vitro and favorable safety profiles in monkeys and mice. A phase I study was conducted to evaluate the safety and pharmacokinetics of six escalating single oral doses of 935U83 in 12 HIV-infected adults. The effect of a high-fat meal on the oral bioavailability of 935U83 was also assessed. The volunteers enrolled had CD4+ cell counts ranging from < 50 to 753 cells per mm3 (median, 198). In the dose range of 100 to 1,500 mg 935U83 was well tolerated by all subjects with no drug-related adverse events reported. No significant clinical or laboratory abnormalities were observed throughout the study. 935U83 was rapidly and well absorbed following oral administration with peak plasma concentrations (Cmax) occurring at 0.8 to 1.3 h postdosing. Mean Cmax and AUC0-infinity values of 935U83 were nearly dose proportional in the 100- to 1,500-mg dose range (from 2.4 to 30 micrograms/ml and from 3.4 to 59 h.micrograms/ml, respectively). Elimination of 935U83 from the plasma was rapid, with an apparent half-life of 1.3 to 1.7 h which was independent of the dose level. Administration of 935U83 with a high-fat meal decreased the rate of 935U83 absorption (mean Cmax decreased by approximately 50% and mean time to Cmax increased by approximately 1 h) but did not affect the extent of oral bioavailability (AUC0-infinity) of 935U83. The 5'-O-glucuronide conjugate was the principal metabolite of 935U83 and was present in the plasma of all volunteers at concentrations lower than 935U83. The molar AUC0-infinity ratio (935U83 glucuronide to the parent compound) was similar across all dose levels (mean, 21 to 27%). At least 60% of the 935U83 dose was absorbed, and approximately an equal percentage of the dose (approximately 30%) was excreted as unchanged 935U83 and as 935U83 glucuronide. Systemic exposure to 935U83 at levels exceeding its average in vitro antiretroviral 50% inhibitory concentration (approximately 0.5 microgram/ml or 1.8 microM) can be achieved after a single oral dose.

Recent benzodiazepine use in depressed patients: a confound of psychoimmunologic studies?

Several studies have indicated that benzodiazepines influence immunity in both animals and humans. As these medications are commonly utilized by and for psychiatric patients, investigation of psycho-immunologic relationships in human psychiatric disorders may be confounded by use of these medications.

METHOD

We undertook an investigation for possible effects of recent benzodiazepine use on depression-immune relationships by comparing 43 patients with current major depressive disorder (MDD) who used benzodiazepines in the week prior to study to 27 patients with current MDD but no use of benzodiazepines in the past month. Both functional and ennumerative measures were investigated.

RESULTS

We found no differences in absolute numbers of lymphocytes or the lymphocyte and NK functional measures. We did find differences between these two groups in the percentage of lymphocytes and of NK cells. Upon further analysis, controlling for symptom severity, these differences were shown to not be independently predicted by benzodiazepine use.

CONCLUSION

Immune measures in subjects with current MDD and recent benzodiazepine use did not differ from those without such recent use. Therefore, such recent use is unlikely to confound PNI results.

Differentiation of central nervous system lesions in AIDS patients using positron emission tomography (PET)

To determine if positron emission tomography (PET) imaging using F-18 fluorodeoxyglucose (FDG) can accurately distinguish between malignant and infectious central nervous system (CNS) mass lesions in patients with human immunodeficiency virus (HIV) infection, a prospective case series of 18 patients with HIV infection and focal CNS lesions on computed tomography (CT) or magnetic resonance (MR) scans was analysed. The patients were divided into 3 groups based on biopsy results, serology and response to therapy. Group 1 consisted of 8 patients with infectious lesions (4 with toxoplasmosis, 2 with neurosyphilis, 2 with progressive multifocal leukoencephalopathy (PML)). Group 2 consisted of 5 patients with biopsy proven CNS lymphoma. Group 3 consisted of 5 patients with presumed CNS lymphoma. Patients underwent FDG-PET studies as an adjunctive diagnostic procedure. The metabolic activity of each patient's lesion was graded using both a qualitative visual score and a semi-quantitative count ratio comparing the lesion with contralateral brain. CNS lesions diagnosed as lymphomas had statistically higher visual scores (P = 0.001) and count ratios (P = 0.002) than CNS lesions diagnosed as infections. FDG-PET could accurately differentiate lymphoma from infections in 16 of 18 cases. Two cases of PML had high metabolic activity and could not be differentiated from lymphoma. FDG-PET shows great promise in differentiating lymphoma from infectious lesions in the CNS of patients with HIV infection. If larger prospective studies confirm this impression, more specific and rapid treatment of CNS lesions could be performed and perhaps obviate the need for brain biopsy in many cases.

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.

HIV-1 RNA levels and the development of clinical disease. North American Lamivudine HIV Working Group

OBJECTIVE

To assess the prognostic value of HIV RNA levels for predicting clinical disease independently of the CD4 lymphocyte count in patients on antiretroviral therapy.

DESIGN

Cohort of HIV-infected patients from two trials of lamivudine therapy.

PATIENTS

For 620 patients randomized in the North American NUCA3001 and NUCA3002 trials of lamivudine, HIV RNA levels were measured (median, seven measures per patient) and CD4 counts were assessed at a central laboratory (median, 13 counts per patient). Patients were in the 1993 Centers for Disease Control and Prevention (CDC) stages A (n = 439), B (n = 135) or C (n = 46) at baseline.

OUTCOME MEASURES

For patients who were in CDC stage A at baseline we considered the ability of HIV RNA levels and CD4 counts to predict the development of CDC stage B or C disease. A Cox proportional hazards model was used. In a second analysis, patients who were AIDS-free at baseline were considered, and the endpoint was AIDS (CDC stage C).

RESULTS

Patients' initial CD4 counts ranged (5-95% centiles) from 104 to 529 x 10(6)/l (median, 274 x 10(6)/l) and HIV RNA levels from 1900 to 339680 copies/ml (median, 44240 copies/ml). For the first analysis, with CDC stage B or C disease as endpoint, both the most recent HIV RNA level and CD4 count predicted the development of clinical disease [relative hazard (RH) for HIV RNA, 1.96 per 10-fold difference in HIV RNA; 95% confidence interval (CI), 1.41-2.73; P = 0.0001; and RH for CD4 count, 1.82 per twofold difference in CD4 count; 95% CI, 1.27-2.56; P = 0.0009]. When both HIV RNA and CD4 count were included in a multiple regression model, both markers provided information additional to that given by the other (RH for HIV RNA, 1.75; 95% CI, 1.23-2.50; P = 0.002; and RH for CD4 count, 1.40; 95% CI, 0.95-2.07; P = 0.09). In the second analysis, with AIDS as endpoint, both HIV RNA level (P = 0.02) and CD4 count (P = 0.004) were independently associated with clinical progression. These results were essentially unchanged after adjustment for treatment arm (zidovudine/lamivudine versus control arms).

CONCLUSION

The HIV RNA level shows ability to predict the development of clinical disease and may thus be of importance in addition to the CD4 count in patient monitoring.