Treatment of recurrent hepatitis C infection after liver transplantation with combination of pegylated interferon alpha2b and ribavirin: an open-label series

BACKGROUND

Hepatitis C virus (HCV) recurrence after orthotopic liver transplantation (OLT) is universal. We aimed to evaluate the efficacy and safety of pegylated interferon (PEG-IFN) and ribavirin (RIB) in the treatment of post-OLT HCV recurrence.

METHODS

Thirty-seven patients with recurrent HCV after OLT were screened and began treatment. Nineteen patients have completed therapy. PEG-IFN was started at a dose of 0.5 microg/kg per week and titrated toward a maximum dose of 1.5 microg/kg per week. RIB was started at a dose of 400 mg per day and titrated toward a maximum of 1000 mg per day, as tolerated. Therapy continued for 1 year after HCV replication was undetectable by reverse transcriptase-polymerase chain reaction and was discontinued if there was no virologic clearance at 48 weeks.

RESULTS

Twelve patients (63%) completed the combination regimen. Therapy was discontinued in seven (37%) patients. Seven patients (37%) had undetectable viral load at the end of treatment. Of those, five patients (26%) had sustained viral response 6 months after discontinuation of therapy. Five patients (26%) had no virologic response. Necro-inflammatory score declined from 5.22 to 2.89 (P=0.05) in nonresponders versus 6.8 to 2.6 (P<0.01) in responders. Fibrosis stage did not change in either group. Genotype 1-infected patients had a lower likelihood of attaining end of treatment or sustained viral response (P<0.05 for both).

CONCLUSIONS

Post-OLT HCV recurrence can be safely treated with PEG-IFN and RIB. Bone marrow toxicity, depression, and rejection are limiting factors that require aggressive management. There was short-term histologic benefit to the use of this regimen, even in those patients without viral clearance.

Hepatitis C virus recurrence in living donor liver transplant recipients

Recurrence of hepatitis C virus (HCV) after liver transplantation (LT) is a universal phenomenon. Recent reports have suggested an earlier and more aggressive recurrence in the living donor liver transplant (LDLT) population. The aim of this study was to compare the histological recurrence of HCV after LDLT versus deceased donor transplantation (DDT). Twenty-nine patients underwent LT for HCV-related end-stage liver disease at our institution between April 2001 and March 2003 (42 months). Twenty patients underwent DDT, and nine patients LDLT. Laboratory data were collected on a weekly to biweekly basis and HCV PCR was performed before LT and 3-4 months and yearly post-LT. Liver biopsies were performed as needed and per institutional protocol at 7 days, at 4 months, and yearly thereafter. All biopsies were evaluated by a single pathologist and scored for rejection (Banff score) and chronic hepatitis (Ishak score system). The predominant genotype in the DDT and LDLT groups was genotype 1 (DDT = 70%, LDLT = 79%). HCV RNA titers pre-LT and 3-4 months after LT did not differ. The incidence of rejection was higher in the DDT group (P < 0.05). There was a trend toward improved Ishak stage and grade in the LDLT group at 4 and 12 months post-LT, however, this trend did not reach statistical significance. No histological difference in the recurrence or severity rate was observed at 4 or 12 months post-LT in the DDT group vs. the LDLT group.

Management of Barrett's oesophagus in 2001 in Ireland

BACKGROUND

Endoscopic surveillance of patients with Barrett's oesophagus is recommended to detect early carcinoma. The practice patterns of endoscopists since the publication of more recent management guidelines remain unknown.

METHODS

All endoscopists (n=68) in the Irish Medical Directory and their trainees were sent a postal questionnaire on Barrett's surveillance.

RESULTS

Fifty-five per cent (30/54) perform surveillance on all patients with Barrett's oesophagus and 38% on selected patients. In patients with no dysplasia, repeat endoscopy was more commonly practiced annually (28/54) than every two to three years (23/54). Surgeons were more likely to perform surveillance annually than gastroenterologists (75% vs 40%). Only 26% of endoscopists took four-quadrant biopsies every 2 cm. Intervention was recommended by a majority (28/54) of endoscopists in a patient with high grade dysplasia. A majority of respondents (47/54) would have surveillance if they were found to have Barrett's oesophagus.

CONCLUSION

Most endoscopists in Ireland do not adhere to recent guidelines in their management of Barrett's oesophagus. Surgical endoscopists perform surveillance more frequently than their medical colleagues.

Neuropsychometric outcome following aortic arch surgery: a prospective randomized trial of retrograde cerebral perfusion

BACKGROUND

Aortic surgery requiring hypothermic circulatory arrest is associated with a high incidence of brain injury. However, knowledge of neuropsychometric outcome is limited. Retrograde cerebral perfusion has become a popular adjunctive technique to hypothermic circulatory arrest. The aim of this study was to assess neuropsychometric outcome and compare the 2 techniques.

METHODS

In a prospective randomized trial, 38 patients requiring elective aortic arch surgery were allocated to either hypothermic circulatory arrest plus retrograde cerebral perfusion or hypothermic circulatory arrest alone. Neuropsychometric testing was performed preoperatively, and at 6 weeks and 12 to 24 weeks postoperatively. Deficit was defined as a 20% decline in 2 tests or more. Standardized Z scores were calculated for each patient and test. Eighteen patients underwent hypothermic circulatory arrest and 20 patients underwent hypothermic circulatory arrest plus retrograde cerebral perfusion. The mean cardiopulmonary bypass, hypothermic circulatory arrest, and retrograde cerebral perfusion durations were 169, 30, and 25 minutes, respectively.

RESULTS

There were 2 deaths and 2 neurological deficits. At 6 weeks postoperatively, 77% of the hypothermic circulatory arrest group and 93% of the hypothermic circulatory arrest plus retrograde cerebral perfusion group had a deficit (P =.22). At 12 weeks this was reduced to 55% and 56%, respectively (P =.93). There was a worse total Z test score in the hypothermic circulatory arrest plus retrograde cerebral perfusion group at 12 weeks (P =.05). Neuropsychometric change did not correlate with hypothermic circulatory arrest duration, presence of aortic atheroma, cannulation technique, or procedure.

CONCLUSIONS

Hypothermic circulatory arrest plus/minus retrograde cerebral perfusion is associated with a high incidence of neuropsychometric change despite ostensibly normal clinical outcomes and apparently safe arrest duration. Retrograde cerebral perfusion did not improve outcome in this small study.

Risk of prevalent HIV infection associated with incarceration among injecting drug users in Bangkok, Thailand: case-control study

OBJECTIVES

To identify risks for HIV infection related to incarceration among injecting drug users in Bangkok, Thailand.

DESIGN

Case-control study of sexual and parenteral exposures occurring before, during, and after the most recent incarceration.

SETTING

Metropolitan Bangkok.

PARTICIPANTS

Non-prison based injecting drug users formerly incarcerated for at least six months in the previous five years, with documented HIV serostatus since their most recent release; 175 HIV positive cases and 172 HIV negative controls from methadone clinics.

MAIN OUTCOME MEASURE

Injection of heroin and methamphetamine, sharing of needles, sexual behaviour, and tattooing before, during, and after incarceration.

RESULTS

In the month before incarceration cases were more likely than controls to have injected methamphetamine and to have borrowed needles. More cases than controls reported using drugs (60% v 45%; P=0.005) and sharing needles (50% v 31%; P<0.01) in the holding cell before incarceration. Independent risk factors for prevalent HIV infection included injection of methamphetamine before detention (adjusted odds ratio 3.3, 95% confidence interval 1.01 to 10.7), sharing needles in the holding cell (1.9, 1.2 to 3.0), being tattooed while in prison (2.1, 1.3 to 3.4), and borrowing needles after release (2.5, 1.3 to 4.4).

CONCLUSIONS

Injecting drug users in Bangkok are at significantly increased risk of HIV infection through sharing needles with multiple partners while in holding cells before incarceration. The time spent in holding cells is an important opportunity to provide risk reduction counselling and intervention to reduce the incidence of HIV.

5,000 kidney transplants--a single-center experience

Between 6/1963 and 12/1998, 5,069 kidney transplants were done at the University of Minnesota. Of these, about half have been living donor, half cadaver. The majority (83%) have been primary transplants. Recipients were grouped in 6 eras based on changes in our immunosuppressive protocols--6/63-12/67 (n = 98); 1/68-7/79 (n = 1,188); 8/79-6/84 (n = 789); 7/84-9/90 (n = 1,006); 10/90-12/95 (n = 1,050; 1/96-12/98 (n = 718)--and their outcomes were compared. Recent eras contained a higher proportion of recipients aged > 50. Since the inception of the program, there has been a steady improvement in actuarial patient survival, graft survival, and death-censored graft survival. Short-term outcome for primary and retransplant recipients has been similar; however, long-term outcome seems worse for retransplant recipients. Importantly, acute rejection and infectious death have become rare causes of graft loss. Chronic rejection and death with function (most often due to a cardiovascular event) have become the predominant causes of graft loss. Recent changes in immunosuppressive protocols (Era VI) have included more aggressive attempts to maintain CsA levels > 150 ng/ml (by HPLC) in the first 3 months and the substitution of mycophenolate mofetil for azathioprine. As a result, the incidence of acute and chronic rejection has decreased and graft survival has improved.

Serological survey for Ehrlichia canis in urban dogs from the major population centres of northern Australia

OBJECTIVE

To detect evidence of Ehrlichia canis infection of dogs from the major population centres of northern Australia, if present.

DESIGN

Serological investigation for E. canis.

PROCEDURE

The sera of 316 domestic dogs, collected from the northern Australian population centres of Townsville, Cairns, Darwin, Kununurra and Broome from May 1997 to August 1999, were investigated for evidence of infection with E. canis. Samples were tested for antibodies to E. canis using an indirect fluorescent antibody (IFA) test. The buffy coats from blood of dogs whose serum reacted in the IFA test were subsequently tested with a nested PCR to detect E. canis DNA. When available, blood from these dogs was injected into suckling mice, which were then examined for clinical disease and tested for the presence of E. canis antibodies.

RESULTS

Of the 316 samples tested seven reacted in the IFA test for E. canis. None of the dogs from which these samples were obtained exhibited clinical signs of acute or chronic ehrlichiosis. The six positive samples available for testing were negative when tested with the nested PCR. Suckling mice inoculated with blood from three of the dogs whose serum was positive by IFA test showed no signs of clinical disease nor did their give positive reactions in the IFA test.

CONCLUSIONS

No evidence of E. canis infection was confirmed in any of the dogs examined. Northern Australia would appear to remain free of this obligate parasite.

Fanconi anemia proteins localize to chromatin and the nuclear matrix in a DNA damage- and cell cycle-regulated manner

Fanconi anemia (FA) is a genetic disease characterized by congenital defects, bone marrow failure, and cancer susceptibility. Cells from patients with FA exhibit genomic instability and hypersensitivity to DNA cross linking agents such as mitomycin C. Despite the identification of seven complementation groups and the cloning of six genes, the function of the encoded gene products remains elusive. The FancA (Fanconi anemia complementation group A), FancC, and FancG proteins have been detected within a nuclear complex, but no change in level, binding, or localization has been reported as a result of drug treatment or cell cycle. We show that in immunofluorescence studies, FancA appears as a non-nucleolar nuclear protein that is excluded from condensed, mitotic chromosomes. Biochemical fractionation reveals that the FA proteins are found in nuclear matrix and chromatin and that treatment with mitomycin C results in increase of the FA proteins in nuclear matrix and chromatin fractions. This induction occurs in wild-type cells and mutant FA-D (Fanconi complementation group D) cells but not in mutant FA-A cells. Immunoprecipitation of FancA protein in chromatin demonstrates the coprecipitation of FancA, FancC, and FancG, showing that the FA proteins move together as a complex. Also, fractionation of mitotic cells confirms the lack of FA proteins in chromatin or the nuclear matrix. Furthermore, phosphorylation of FancG was found to be temporally correlated with exit of the FA complex from chromosomes at mitosis. Taken together, these findings suggest a role for FA proteins in chromatin and nuclear matrix.

Provider assessment of adherence to HIV antiretroviral therapy

BACKGROUND

Adherence assessment is an essential component of monitoring HIV antiretroviral therapy. Prior studies suggest that medical providers frequently estimate individual patient adherence inaccurately.

OBJECTIVE

We compared provider estimates of nonadherence to antiretroviral therapy with unannounced pill counts and structured patient interviews to determine the accuracy of adherence information obtained by providers and patients.

DESIGN, SETTING, AND PARTICIPANTS

Comparison of three adherence measures in homeless or marginally housed persons receiving HIV antiretroviral therapy (n = 45) and their providers (n = 35).

MEASUREMENTS

Provider estimate of percentage of pills taken; three successive patient structured reports of number of doses missed in the last 3 days; and three successive unannounced pill counts.

RESULTS

13% (95% confidence interval [CI], 4%-22%) of patients were not following their regimen as directed. Provider-adherence estimate explained only 26% (95% CI, 6%-47%) of the variation in pill count adherence, whereas patient report explained 72% (95% CI, 52%-96%). The sensitivity and specificity of provider estimates of nonadherence, defined as <80% of pills taken by pill count, were 40% and 85%, respectively. The sensitivity and specificity of patient interview were 72% and 95%, respectively.

CONCLUSIONS

Provider estimate of adherence was inaccurate whereas structured patient report was more closely related to pill count. Structured assessment over several short intervals may improve accuracy of adherence assessment in clinical practice.

Cooperation, control, and concession in meerkat groups

"Limited control" models of reproductive skew in cooperative societies suggest that the frequency of breeding by subordinates is determined by the outcome of power struggles with dominants. In contrast, "optimal skew" models suggest that dominants have full control of subordinate reproduction and allow subordinates to breed only when this serves to retain subordinates' assistance with rearing dominants' own litters. The results of our 7-year field study of cooperative meerkats, Suricata suricatta, support the predictions of limited control models and provide no indication that dominant females grant reproductive concessions to subordinates to retain their assistance with future breeding attempts.

Tubulin stimulates adenylyl cyclase activity in C6 glioma cells by bypassing the beta-adrenergic receptor: a potential mechanism of G protein activation

While the cytoskeleton is known to play several roles in the biology of the cell, one role, which has been revealed only recently, is that of a participant in the signal transduction process. Tubulin binds specifically to the alpha subunits of Gs (stimulatory GTP-binding regulatory protein of adenylyl cyclase), Gi1 (inhibitory protein of adenylyl cyclase), and Gq and transactivates those molecules through direct transfer of GTP. The relevance of this transactivation process to G proteins which are normally activated by a neurotransmitter-occupied receptor is the subject of this study. C6 glioma cells, made permeable with saponin, retained tight coupling between Gs and the beta-adrenergic receptor. Although 5-guanylylimidodiphosphate (GppNHp) was incapable of activating Gs (and subsequently, adenylyl cyclase) in the absence of agonist, tubulin with GppNHp bound (tubulin-GppNHp) activated adenylyl cyclase with an EC(50) of 30 nM. Desensitization of beta-adrenergic receptors by isoproterenol exposure had no effect on the ability of tubulin-GppNHp to activate Gs and adenylyl cyclase. When the photoaffinity GTP analog, azidoanilido GTP (AAGTP; P3(4-azidoanilido)-P1-5'-GTP), was added to C6 membranes or permeable C6 cells, it was only weakly incorporated by G alpha s in the absence of isoproterenol. When the same concentration of dimeric tubulin with AAGTP bound was introduced, AAGTP was transferred from tubulin to G alpha s, activating the latter species. Similar 'preferential' activation of G alpha s by tubulin-AAGTP versus the free nucleotide was seen using purified components. Thus, membrane-associated tubulin may serve to activate G alpha s, independent of signals not normally coupled to that protein. Tubulin may act as an agent to link a variety of membrane-associated signalling systems.

From coping with life to coping with death: problematic integration for the seriously ill elderly

Decisions made by and for elderly patients nearing death frequently perpetuate unwanted suffering and dependence. This article extends the argument that Babrow's (1992, 1995) problematic integration theory can provide insights into why communication fails to produce desired outcomes for such patients. Open-ended responses obtained in face-to-face interviews with 142 elderly dialysis patients and mailed surveys of 393 dialysis unit nurses were examined to better understand how patients and nurses reconciled incompatible probabilistic and evaluativejudgments. Results indicate that patients seek information that will enable them to cope with debilitating dialysis treatments rather than information nurses believe is necessary for them to make informed choices about whether to undergo such treatments. The tension between the information patients want to successfully cope with life and the information they need to decide intelligently about treatments that forestall death constitutes a key reason why communication about end-of-life issues is frequently flawed. Our analysis of these communication flaws leads to specific recommendations for how this tension can be eased, which in turn may better prepare patients to make the transition from coping with life to coping with death.

Pre-emptive transplants for patients with renal failure: an argument against waiting until dialysis

BACKGROUND

Pre-emptive kidney transplants have not been favored in some centers because of concern about possible increased noncompliance and allegedly inferior long-term results. We analyzed our experience with pre-emptive kidney transplants to determine whether such concerns are justified.

PATIENTS AND METHODS

Between January 1, 1984, and June 30, 1998, we performed 1849 adult primary kidney transplants: 385 pre-emptive (recipients not undergoing dialysis, ND) and 1464 non-pre-emptive (recipients undergoing dialysis, D). Results were subdivided by donor source: cadaver (CAD) and living donor (LD). ND recipients tended to be younger, but otherwise, the two groups were similar. Posttransplantation quality of life in recipients was evaluated using the nationally standardized Short Form Health Survey (SF-36). The posttransplantation employment status of the recipients was also evaluated.

RESULTS

The patient survival rate 5 years posttransplantation was significantly better for ND (vs. D) recipients for both CAD (92.6% vs. 76.6%, P=0.001) and LD (93.3% vs. 89.5%, P=0.02) transplants. The 5-year patient survival rate was significantly higher for ND recipients compared with recipients undergoing dialysis for < 1, 1-2, and > 2 years pretransplantation for both CAD (P=0.0005) and LD (P=0.0001) transplants. The graft survival rate 5 years posttransplantation was similar between ND and D recipients for CAD transplants, but significantly better for ND (vs. D) recipients of LD transplants (92.3% vs. 84.8%, P=0.006). For CAD transplants, the 5-year graft survival rate was not different when ND recipients were compared with recipients undergoing dialysis for < 1, 1-2, and > 2 years pretransplantation; for LD transplants it was significantly higher for ND recipients compared with recipients undergoing dialysis for < 1, 1-2, and > 2 years pretransplantation (P=0.04). The incidence of acute and chronic rejection was no different between ND and D recipients for either CAD or LD transplants, and it was also not affected by the pretransplantation time undergoing dialysis. Graft loss secondary to the recipient's discontinuation of immunosuppressive therapy (a crude estimate of compliance) was similar between ND and D recipients. Five years posttransplantation, the SF-36 scores regarding the recipient's quality of life and the employment status were similar for ND compared with D recipients, regardless of donor source.

CONCLUSIONS

ND recipients do not seem to have higher rates of noncompliance than D recipients. Results for ND recipients seem to be superior than for D recipients, supporting the contention that renal failure patients should, if possible, undergo transplantation before dialysis.

Adherence to protease inhibitors, HIV-1 viral load, and development of drug resistance in an indigent population

OBJECTIVE

To examine the relationship between adherence, viral suppression and antiretroviral resistance in HIV-infected homeless and marginally housed people on protease inhibitor (PI) therapy.

DESIGN AND SETTING

A cross-sectional analysis of subjects in an observational prospective cohort systematically sampled from free meal lines, homeless shelters and low-income, single-room occupancy (SRO) hotels.

PARTICIPANTS

Thirty-four HIV-infected people with a median of 12 months of PI therapy.

MAIN OUTCOMES

Adherence measured by periodic unannounced pill counts, electronic medication monitoring, and self-report; HIV RNA viral load; and HIV-1 genotypic changes associated with drug resistance.

RESULTS

Median adherence was 89, 73, and 67% by self-report, pill count, and electronic medication monitor, respectively. Thirty-eight per cent of the population had over 90% adherence by pill count. Depending on the measure, adherence explained 36-65% of the variation in concurrent HIV RNA levels. The three adherence measures were closely related. Of 20 genotyped patients who received a new reverse transcriptase inhibitor (RTI) when starting a PI, three had primary protease gene substitutions. Of 12 genotyped patients who received a PI without a new RTI, six had primary protease gene substitutions (P < 0.03).

CONCLUSION

A substantial proportion of homeless and marginally housed individuals had good adherence to PI therapy. A strong relationship was found between independent methods of measuring adherence and concurrent viral suppression. PI resistance was more closely related to the failure to change RTI when starting a PI than to the level of adherence.

Tracking and follow-up of marginalized populations: a review

Maintaining study cohorts is a key element of longitudinal research. Participant attrition introduces the possibility of bias and limits the generalizability of a study's findings, but with appropriate planning it is possible to sustain contact with even the most transient participants. This paper reviews the essential elements of tracking and follow-up of marginalized populations, which are (1) collection of contact information, (2) thorough organization of tracking efforts, (3) attention to staff training and support, (4) use of phone and mail follow-up, (5) use of incentives, (6) establishing rapport with participants, (7) assurance of confidentiality, (8) use of agency tracking, (9) use of field tracking, and (10) attention to safety concerns. Diligent application of these tracking strategies allows researchers to achieve follow-up rates of 75 percent to 97 percent with vulnerable populations such as homeless, mentally ill adults, injection drug users, and runaway youth.

Comparison of the plaque test and reverse transcription nested PCR for the detection of FMDV in nasal swabs and probang samples

In order to compare the sensitivity of assays for the diagnosis of foot-and mouth disease (FMD), a cell suspension plaque test on BHK21-CT cells and a reverse transcription nested PCR (RT-nPCR) were used to examine 485 nasal swabs and 227 probang samples obtained from FMDV-infected cattle during vaccine potency tests. In nasal swabs, FMDV could be detected by both tests before the onset of clinical symptoms. However, after two weeks p.i., FMDV was only detected routinely in the probang samples. Examination of nasal swabs revealed a higher number of infected animals using RT-nPCR than by the use of the plaque test. Both tests gave approximately equivalent results with the probang samples.

Q-wave versus non-Q wave myocardial infarction: a meaningless distinction

The whole subject can thus be summed up in two statements. 1. Every appropriately designed study comparing first Q and NQMI's has found no difference in post-MI course of the two categories and no foundation for the common notion that the NQMI is a uniquely "unstable" entity, to be classed with unstable angina in terms of prognosis and management. Nine such studies have been published. On the other hand, all studies alleging the "unstable" character of the NQMI have been invalidated by major flaws, chief among them the comparison of undifferentiated mixtures of first and subsequent infarcts with widely differing mortality and morbidity. This confusion is further compounded by the fact that subsequent infarcts generate Qwaves less than half as often as first infarcts. 2. All current studies indicate that there is no benefit to an invasive as compared with a conservative protocol for management of NQMI. Since the characterization of an infarct as "non-Q' conveys no therapeutic implications, the classification becomes irrelevant and should be discarded. Two quotations sum the whole matter succinctly. Moss (63) commented that "The Q-wave versus non-Q-wave categorization does not provide sufficient sensitivity, specificity, or predictive accuracy about the subsequent clinical course of patients with a first myocardial infarction to use it as reliable data in the clinical decision-making process." Surawicz (64) put the matter even more concisely: ". . . a non-Qwave MI is not a unique entity: rather it is a smaller and less extensive MI." In a word, the magnitude of a myocardial infarction should be judged on anatomical and functional considerations rather than on the designation of Qwave versus non-Qwave infarction.

Reduction in tuberculin skin-test conversions among medical house staff associated with improved tuberculosis infection control practices

OBJECTIVE

To assess the efficacy of an infection control program as measured by tuberculin skin-test (TST) conversion rates in medical house staff.

DESIGN

Observational study.

SETTING

University-based hospital in New York City serving a large indigent population.

PARTICIPANTS

Medical house staff.

INTERVENTIONS

TST conversions were measured every 6 months in medical house staff from June 1992 to June 1994. Compliance with the isolation policy was measured by identifying room locations 24 hours after admission of patients who had Mycobacterium tuberculosis recovered from respiratory specimens.

RESULTS

The TST conversion rate decreased from 5.8 to 0, 2.3, and 0 per 100 person years of exposure in successive 6-month periods. The estimated annual TST conversion rate among interns fell from 7 per 100 person years in June 1992 to 0 per 100 person years in June 1993 and 0 per 100 person years in June 1994 (P < .029). The proportion of patients with pulmonary tuberculosis who were isolated in negative-pressure rooms increased from 38% to 75% over the study period (P < .01).

CONCLUSION

Development of a multifaceted infection control program can decrease the risk of nosocomial tuberculosis infection in medical house staff.

Independent origin of mono-rifampin-resistant Mycobacterium tuberculosis in patients with AIDS

Historically, infections caused by Mycobacterium tuberculosis have been treated simultaneously with isoniazid and rifampin. As a consequence of this combined therapy, strains resistant only to rifampin were rarely recovered. However, recently there has been an increasing number of reports describing HIV-positive patients infected with mono-rifampin-resistant M. tuberculosis strains. Organisms cultured from seven patients (including six with AIDS) with infections caused by mono-rifampin-resistant M. tuberculosis, and seen at one New York City hospital, were analyzed by molecular techniques to test the hypothesis that dissemination of a single clone had occurred. IS6110 DNA fingerprinting and automated DNA sequencing of a region of the RNA polymerase beta subunit structural gene (rpoB) containing mutations that confer rifampin resistance showed that all organisms independently acquired the mono-rifampin-resistant phenotype. Molecular analysis of mono-rifampin-resistant organisms cultured from 13 additional patients in New York City confirmed independent strain origin. The data rule out the possibility of person-to-person strain transmission among these patients, and they suggest that host factors such as poor compliance with antituberculosis medications or decreased absorption of rifampin have been a driving force in the origin of these strains.

Effect of cyclosporine on renal function in kidney transplant recipients: a 12-year follow-up

Nephrotoxicity remains a concern for patients on long-term cyclosporine. We have previously reported on renal function in a cohort of kidney transplant recipients followed up to 10 years posttransplant. The current study extends the analysis to 12 years. We find no evidence of cyclosporine-induced renal failure.

Tuberculosis knowledge among New York City injection drug users

Structured interviews measuring tuberculosis knowledge were administered to 494 New York City injection drug users, 31% of whom reported a history of having a reactive tuberculin skin test. Medical records review of a subsample confirmed the validity of self-reported data. Most respondents understood the mechanisms of tuberculosis transmission. Three fourths of the subjects did not fully understand the distinction between a reactive skin test and active tuberculosis, but those who reported a history of skin test reactivity were twice as likely to understand this distinction. Forty percent of subjects did not understand the importance of medication adherence. Misunderstandings, based on a recent lack of tuberculosis education, may contribute to the fear and confusion that interfere with efforts to control tuberculosis.

Evidence of genetic heterogeneity in Romano-Ward long QT syndrome. Analysis of 23 families

BACKGROUND

The Romano-Ward long-QT Syndrome (LQTS) is an autosomal dominant inherited trait characterized by prolonged QT interval on ECG, life-threatening arrhythmias, syncope, and sudden death in affected individuals. A gene responsible for this disorder has been shown to be linked to the Harvey ras-1 locus (H-ras-1) DNA marker on the short arm of chromosome 11 (11p) in 7 families. The purpose of this study was to determine, by analyzing 23 families with LQTS for linkage to chromosome 11p, whether evidence exists for more than one gene causing LQTS (ie, locus heterogeneity).

METHODS AND RESULTS

Twenty-three families (262 family members) were clinically evaluated using medical histories, ECGs, and Holter recordings. Each corrected QT interval (QTc) were determined using Bazett's formula. Blood for DNA extraction and cell line immortalization was obtained after informed consent. Southern blotting and polymerase chain reaction were performed, and linkage analysis carried out using the LINKAGE computer program (v 5.03). Genetic heterogeneity was determined using the HOMOG 2 (v 2.51) computer program. Twenty-three families were studied for evidence of linkage to chromosome 11p using the H-ras-1 locus probe pTBB-2 and multiple flanking markers, including tyrosine hydroxylase (TH). Two-point linkage analysis using pTBB-2 and TH markers was consistent with linkage in 15 of 23 families, with the maximum single-family LOD score of +3.038 occurring at theta = 0. However, 8 of 23 families had negative LOD scores, with the values in 4 families being less than -2 at theta = 0, consistent with exclusion of linkage. Analysis with the HOMOG program was consistent with genetic heterogeneity (P < .0001). Multipoint linkage data using pTBB-2 and TH were also examined for evidence of heterogeneity. HOMOG analysis of multipoint LOD scores from 100 cM surrounding the H-ras-1 locus also supported heterogeneity (P < .001).

CONCLUSIONS

In the 23 families with LQTS analyzed for linkage to the H-ras-1 locus on chromosome 11p15.5, 15 of 23 families had LOD scores consistent with linkage. The remaining 8 of 23 families had negative LOD scores, 4 of which were definitively excluded from linkage. Thus, genetic heterogeneity is definitively (P < .001) demonstrated for this disorder.

Risk factors for anal human papillomavirus infection and anal cytologic abnormalities in HIV-positive and HIV-negative homosexual men

Men with advanced human immunodeficiency virus (HIV) disease have a high prevalence of anal human papillomavirus (HPV) infection and potentially precancerous anal disease. To characterize prevalence of and risk factors for anal HPV infection and anal cytologic abnormalities, 37 HIV-positive and 28 HIV-negative participants in the San Francisco General Hospital Cohort Study were studied. A questionnaire was administered, followed by an anal examination consisting of two consecutive anal swabs for cytology and HPV DNA hybridization, and anoscopy with biopsy of visible lesions. Ten of 28 (36%) HIV-negative men and 19 of 37 (51%) HIV-positive men had anal HPV infection (p = 0.32). Risk factors for anal HPV infection included HIV positivity with a CD4 count < 200/mm3 (p = 0.03) and a history of smoking (p = 0.03). Abnormal anal cytology was found in 2 of 26 (8%) HIV-negative men and 10 of 36 (28%) HIV-positive men with cytology adequate for interpretation (p = 0.09). Risk factors for abnormal anal cytology included HIV positivity with a CD4 count < 200/mm3 (p = 0.006) and current smoking (p = 0.03). We conclude that the risk of development of anal disease and HPV infection was highest among HIV-positive men with a CD4 count of < 200/mm3, and that smoking may play a role in the pathogenesis of anal disease.

Changes in AIDS survival time in two San Francisco cohorts of homosexual men, 1983 to 1993

BACKGROUND

During the first decade since the recognition of the acquired immunodeficiency syndrome (AIDS), new therapies have been introduced and the frequency of clinical manifestations has changed. The impact of these changes on AIDS survival, however, has not been well characterized.

DESIGN

A prospective cohort study of the outcomes of human immunodeficiency virus (HIV) infection.

SETTING

Homosexual and bisexual men residing in San Francisco, Calif, recruited in 1983 and 1984 for two prospective studies and followed up for more than 9 years with clinical examinations.

PARTICIPANTS

A total of 761 HIV-positive homosexual and bisexual men.

MAIN OUTCOME MEASURES

Survival time from a CD4 lymphocyte count at 0.20 x 10(9)/L (200/microL) and from a clinical AIDS diagnosis to death.

RESULTS

Median survival time from a CD4 lymphocyte count at 0.20 x 10(9)/L increased from 28.4 months in the October 1983 to November 1986 period to 40.1 months in the November 1986 to November 1988 period and is estimated at 38.1 months in the November 1988 to February 1993 period. Patients diagnosed with Pneumocystis carinii pneumonia (PCP) accounted for most of this increase with a gain in median survival time of 9.7 months (P = .0009), compared with a nonsignificant decline in the survival time of those patients without a PCP diagnosis. Multivariate analysis showed that rate of CD4 lymphocyte loss (P < .001) and receipt of both PCP prophylaxis and antiretroviral therapy (P = .04) were significantly associated with longer survival time, whereas antiretroviral therapy alone was not (P = .81). Time to death from a clinical AIDS diagnosis was 14.7 months in the 1983 to 1986 period, 19.1 months in the 1986 to 1988 period, and an estimated 15.7 months in the 1988 to 1993 period.

CONCLUSIONS

Survival time from a CD4 lymphocyte count at 0.20 x 10(9)/L has improved significantly by about 1 year; yet survival time using the 1987 AIDS case definition has shown small improvement. The largest increase in survival time from a CD4 lymphocyte count at 0.20 x 10(9)/L was in patients diagnosed with PCP, suggesting that PCP prophylaxis and treatment were more important factors in longer survival time than antiretroviral therapy.

Human T cell leukemia virus (HTLV-I/II) serodiagnostic testing: disparate results among a cohort of intravenous drug users

Three hundred and forty-six sera collected over a 2-year period from 154 San Francisco IV drug users were subjected to HTLV-I/II RIPA, Western blot (WB), Du Pont ELISA, and p24 radioimmunoassay (RIA). Tests were performed at separate sites and code not broken until study end. RIPA-positive and -negative controls consisted of Japanese adult T cell leukemia patients, healthy blood donors, and non-IV drug-using HIV-positive men. RIPA identified HTLV-I/II-positive sera not identified by the other tests. Positive RIPAs were noted in 43% of negative ELISAs (n = 279), 34% of negative WBs (n = 243), and 40% of negative RIAs (n = 270). Seventy-two sera were negative by all 3 assays, but were RIPA positive. All sera positive by RIA (n = 76) and WB (n = 67), and 66 of 67 by ELISA, were positive by RIPA. Thirty-five of 36 indeterminate WBs were RIPA positive. Seven samples indeterminate by RIPA were negative by WB and RIA; one of seven was positive by ELISA. In all instances, samples negative by RIPA (n = 154) were ELISA, p24 RIA, and WB negative or indeterminate. We conclude that when studying HTLV-I/II-endemic cohorts, screening ELISA or RIA followed by confirmatory WB or RIPA only of seropositive samples may result in a substantial number of undetected cases. Additional studies focusing on performance characteristics of serodiagnostic tests are needed to ensure accurate inferences are made in assessing HTLV-I/II prevalence rates among high-risk groups. The RIPA may be a uniquely sensitive assay to detect HTLV-I/II gene-encoded products.

Rapamycin: immunosuppression, hyporesponsiveness, and side effects in a porcine renal allograft model

Rapamycin prolongs allograft survival and induces donor-specific tolerance in some small animal transplant models. Large animal studies, however, are limited. We studied rapamycin in a porcine renal allograft model. Donor-recipient combinations were chosen based on high response in pretransplant MLCs. Allografts were anastomosed to the aorta and vena cava and the native kidneys removed. There were 5 treatment groups: (a) no immunosuppression; (b) triple therapy (CsA, 1 mg/kg/day; AZA, 2-3 mg/kg/day; and PRED, 3-4 mg/kg/day); (c) rapamycin (0.75 mg/kg/day i.m.) in carboxymethylcellulose (CMC); (d) rapamycin (0.25 mg/kg/day i.m. in CMC); and (e) a vehicle (CMC) control. Serum creatinine levels were determined every other day. Most allografts were biopsied once a week. Immunosuppression was stopped after 30 days. Mean graft survival in nonimmunosuppressed recipients was 6.8 +/- 3.6 days. Mean graft survival in triple therapy recipients (n = 10) was 45.7 +/- 36 days vs. 59.6 +/- 11.4 days in rapamycin (0.25 mg/kg/day) recipients (n = 7) (P = 0.51). Both triple therapy and rapamycin improved renal allograft survival versus nonimmunosuppressed controls (P = 0.0025 and 0.001, respectively). Serum creatinine levels were significantly lower (P < 0.05) in rapamycin versus triple therapy recipients. We conclude that rapamycin is a potent immunosuppressant in a porcine renal allograft model and may avoid the elevated serum creatinine levels associated with CsA.

Molecular epidemiology and the new tuberculosis

DNA fingerprinting techniques now exist which identify specific strains of Mycobacterium tuberculosis. These techniques may be integrated with conventional epidemiologic approaches to better understand tuberculosis in its modern form. This paper reviews the lessons learned from this approach about the pathogenesis and epidemiology of tuberculosis. In addition, it speculates about the potential future applications of molecular epidemiology, including its use as an adjunct to conventional public health measures.

Phosphotyrosine-containing proteins in the CNS of obese Zucker rats are decreased in the absence of changes in the insulin receptor

The location and quantity of the insulin receptor and its associated tyrosine kinase activity have been examined in the forebrains of lean (Fa/?) and obese (fa/fa) Zucker rats using immunocytochemistry (ICC) and biochemical procedures. These studies were performed in conjunction with ICC and Western blot analysis of phosphotyrosine-containing proteins (PY-proteins). The results from ICC show a similar distribution and content for the insulin receptor among forebrain regions of lean and fatty Zucker rats. Biochemical analysis of the receptor was conducted on the hippocampus. Insulin binding studies using lectin-purified receptor extracts demonstrated similar receptor number and comparable hormone binding affinity for lean and obese animals. Autophosphorylation studies with the receptor extracts from the two groups did not find any differences in the tyrosine kinase activity of insulin receptors. In contrast to the normal findings with the insulin receptor, an abnormality in the obese animals was evident in the content of PY-proteins detected by ICC in the hippocampus, piriform cortex and olfactory bulb. Neurons in these brain regions showed a reduction in staining by an antibody against PY-proteins. Furthermore, Western blots of hippocampal extracts from obese rats demonstrated a reduction in phosphotyrosine content of two proteins of Mr 180 and 130 kD. These findings point to a previously unrecognized alteration in the CNS of the obese, insulin-resistant Zucker rat.

Population-based estimates of antiretroviral therapy and anti-Pneumocystis prophylaxis in San Francisco: 1991

Using data from the San Francisco Men's Health Study and the San Francisco General Hospital Cohort, we derived partially population-based estimates of human immunodeficiency virus (HIV) antiretroviral therapy and Pneumocystis carinii prophylaxis use in HIV-infected men in 1991. Zidovudine, didanosine, and dideoxycytidine were the antiretroviral therapies and aerosolized pentamidine, trimethoprim-sulfamethoxazole, and dapsone were the Pneumocystis prophylaxis evaluated. Among 81 men (29 of whom had AIDS) with < or = 200 CD4 cells, 76 (94%) had ever used and 56 (69%) were currently using an antiretroviral drug; 73 (90%) had ever used and 61 (75%) were currently using Pneumocystis prophylaxis. Among 127 men with 201-499 CD4 cells, 95 (75%) had ever used and 81 (64%) were currently using antiretroviral therapy; 49 (39%) had ever used and 36 (28%) were currently using Pneumocystis prophylaxis. Among 122 men with > or = 500 CD4 cells, 29 (24%) were currently receiving antiretroviral therapy. Forty-three men had discontinued antiretroviral therapy, 29 (67%) because of side effects. Thirty-seven men with < or = 500 CD4 cells had never used antiretroviral drugs: 48% because of feeling well and 28% because of possible side effects. Compared with 1987-1989, there were substantial increases in both antiretroviral therapy and anti-Pneumocystis prophylaxis use.