Population Pharmacokinetics of Piperaquine in Young Ugandan Children Treated With Dihydroartemisinin-Piperaquine for Uncomplicated Malaria

This prospective trial investigated the population pharmacokinetics of piperaquine given with dihydroartemisinin to treat uncomplicated malaria in 107 Ugandan children 6 months to 2 years old, an age group previously unstudied. Current weight-based dosing does not adequately address physiological changes in early childhood. Patients were administered standard 3-day oral doses and provided 1,282 capillary plasma concentrations from 218 malaria episodes. Less than 30% of treatments achieved 57 ng/mL on day 7. A three-compartment model with first-order absorption described the data well. Age had a statistically significant effect (P < 0.005) on clearance/bioavailability in a model that accounts for allometric scaling. Simulations demonstrated that higher doses in all children, but especially in those with lower weight for age, are required for adequate piperaquine exposure, although safety and tolerance will need to be established. These findings support other evidence that both weight- and age-specific guidelines for piperaquine dosing in children are urgently needed.

Susceptibility to Buruli ulcer is associated with the SLC11A1 (NRAMP1) D543N polymorphism

Similar to other mycobacterial diseases, susceptibility to Buruli ulcer (Mycobacterium ulcerans infection) may be determined by host genetic factors. We investigated the role of SLC11A1 (NRAMP1) in Buruli ulcer because of its associations with both tuberculosis and leprosy. We enrolled 182 Buruli ulcer patients (102 with positive laboratory confirmation) and 191 healthy neighbourhood-matched controls in Ghana, and studied three polymorphisms in the SLC11A1 gene: 3' UTR TGTG ins/del, D543N G/A, and INT4 G/C. Finger prick blood samples from study subjects were dried on filter papers (FTA) and processed. D543N was significantly associated with Buruli ulcer: the odds ratio (adjusted for gender, age, and region of the participant) of the GA genotype versus the GG genotype was 2.89 (95% confidence intervals (CI): 1.41-5.91). We conclude that a genetic polymorphism in the SLC11A1 gene plays a role in susceptibility to develop Buruli ulcer, with an estimated 13% population attributable risk.

Leptospirosis among patients presenting with dengue-like illness in Puerto Rico

Leptospirosis is difficult to distinguish from dengue fever without laboratory confirmation. Sporadic cases/clusters of leptospirosis occur in Puerto Rico, but surveillance is passive and laboratory confirmation is rare. We tested for leptospirosis using an IgM ELISA on sera testing negative for dengue virus IgM antibody and conducted a case-control study assessing risk factors for leptospirosis, comparing clinical/laboratory findings between leptospirosis (case-patients) and dengue patients (controls). Among 730 dengue-negative sera, 36 (5%) were positive for leptospirosis. We performed post mortem testing for leptospirosis on 12 available specimens from suspected dengue-related fatalities; 10 (83%) tested positive. Among these 10 fatal cases, pulmonary hemorrhage and renal failure were the most common causes of death. We enrolled 42 case-patients and 84 controls. Jaundice, elevated BUN, hyperbilirubinemia, anemia, and leukocytosis were associated with leptospirosis (p < .01 for all). Male sex, walking in puddles, rural habitation, and owning horses were independently associated with leptospirosis. Epidemiological, clinical, and laboratory criteria may help distinguish leptospirosis from dengue and identify patients who would benefit from early antibiotic treatment.

Etiology of pulmonary infections in predominantly HIV-infected adults with suspected tuberculosis, Botswana

SETTING

In countries with high HIV rates, diagnosis of lower respiratory disease etiology is both challenging and clinically important.

OBJECTIVE

To determine the etiology of lower respiratory tract disease among persons with suspected tuberculosis (TB) and abnormal chest X-rays in a setting with very high HIV seroprevalence.

DESIGN

Cross-sectional prevalence data from a prospective cohort of predominantly hospitalized adults with suspected TB in Botswana, January-December 1997.

RESULTS

Of 229 patients, 86% were HIV-positive and 71% had a pathogen identified. TB was confirmed in 52%, 17% had acute mycoplasma pneumonia, 3% had Pneumocystis carinii, 27% grew a bacterial pathogen from sputum and 8% from blood. Ninety-four per cent of TB diagnoses were made through expectorated sputum and only 5% of TB cases were diagnosed by sputum induction alone. Polymerase chain reaction (PCR) for Mycobacterium tuberculosis had positive and negative predictive values of 94% and 59%, respectively. Male sex, cough < 2 weeks, and tuberculin skin test > or = 5 mm were independently associated with culture-positive TB among persons with negative acid-fast bacilli smears. Co-infection with two or more pathogens occurred in 25%.

CONCLUSIONS

Mycoplasma pneumoniae infection was quite common despite clinical suspicion of TB, and sputum induction and PCR did not significantly improve our ability to diagnose TB, although clinical presentation had some predictive value.

Risk of Mycobacterium tuberculosis infection and disease among health care workers, Chiang Rai, Thailand

SETTING

A provincial referral hospital in northern Thailand, where a cross-sectional study during 1995-1996 reported on the occupational risk of Mycobacterium tuberculosis transmission.

OBJECTIVE

To describe the effectiveness of prevention strategies for nosocomial tuberculosis (TB).

DESIGN

A prospective study among health care workers (HCW) including annual tuberculin skin test (TST) screening and active TB surveillance. Following a comprehensive risk assessment, preventive interventions were implemented targeting HCWs, hospitalised patients, and the hospital environment.

RESULTS

The number of pulmonary TB cases diagnosed increased steadily from 102 in 1990 to 356 in 1999. The TST conversion rate was 9.3 (95% CI 3.3-15) per 100 person-years (py) in 1995-1997, but declined steadily to 2.2 (95% CI 0.0-5.1) in 1999. HCWs first screened within 12 months of employment had higher TST conversion rates (adjusted RR = 9.5, 95% CI 1.8-49.5) compared to those employed for longer than 12 months. The annual rate of active TB per 100 000 HCWs was 536 in 1995-1999.

CONCLUSION

These HCWs were exposed to active TB patients and were at risk for M. tuberculosis infection, particularly during their first 12 months of employment. Implementation of nosocomial TB control measures in 1996 was followed by declining TST conversion rates, despite increasing exposure to active TB patients.

Impact of enhanced notification of tuberculosis laboratory results to minimise treatment delay, Chiang Rai Hospital, Northern Thailand

SETTING

A provincial referral hospital in northern Thailand, where a cross-sectional study from 1995-1996 reported on the occupational risk of Mycobacterium tuberculosis transmission.

OBJECTIVE

To assess the impact of acid-fast bacilli sputum smear-positive results notification to improve tuberculosis (TB) services by documenting the location of sputum collection, completing the TB register immediately, and minimising delays between hospital admission and treatment initiation.

DESIGN

The cohort of smear-positive TB patients identified through laboratory microscopy record reviews from 1994-1999. Time from admission to hospital, laboratory diagnosis of TB, registration for treatment, and initiation of therapy were determined during the implementation of enhancing the laboratory results notification system.

RESULTS

The number of unregistered TB patients fell from 44 cases in 1994 to none in 1999. The time elapsed from admission to treatment initiation decreased from a mean of 5.6 days in 1997 (n = 162) to 3.1 days in 1999 (n = 136) (P < 0.001). This decrease was attributed to a reduction in time between laboratory diagnosis and treatment from 2.7 days in 1997 to 0.6 days in 1999 (P < 0.001).

CONCLUSION

Prompt identification, isolation and treatment of TB patients occurred through an enhanced laboratory notification system. Such systems are inexpensive, improve TB care services and may reduce nosocomial transmission of M. tuberculosis.

Pathology and causes of death in a group of 128 predominantly HIV-positive patients in Botswana, 1997-1998

BACKGROUND

Little is known about causes of death in countries of southern Africa seriously affected by the HIV/AIDS epidemic.

METHODS

After obtaining informed consent, autopsies were performed on 128 mainly hospitalised adults in Francistown, Botswana, between July 1997 and June 1998. Criteria for case selection included those who died before a diagnosis could be established, those whose condition deteriorated unexpectedly during hospitalization, and those who had respiratory disease. This represented 14% of adult medical patients who died in hospital during the study period.

RESULTS

Of the 128 patients, 104 (81%) were HIV-positive. Among HIV-positive patients, the most common pathologic findings were tuberculosis (TB) (40%), bacterial pneumonia (23%), Pneumocystis carinii pneumonia (11%), and Kaposi's sarcoma (11%); these conditions were the cause of death in 38%, 14%, 11%, and 6%, respectively. Of the 40 pulmonary TB cases, 90% also had disseminated extra-pulmonary TB. Chest radiology could not reliably distinguish the pathologies pre-mortem.

CONCLUSIONS

TB was the leading cause of death in our series of HIV-positive adults in Botswana, selected towards those with chest disease; in most, it was widely disseminated. Bacterial pneumonia also played an important role in mortality. Pneumocystis carinii pneumonia was present, but relatively uncommon.

Leptospirosis mimicking acute cholecystitis among athletes participating in a triathlon

Leptospirosis, a disease acquired by exposure to contaminated water, is characterized by fever accompanied by various symptoms, including abdominal pain. An acute febrile illness occurred in athletes who participated in an Illinois triathlon in which the swimming event took place in a freshwater lake. Of 876 athletes, 120 sought medical care and 22 were hospitalized. Two of the athletes had their gallbladders removed because of abdominal pain and clinical suspicion of acute cholecystitis. We applied an immunohistochemical test for leptospirosis to these gallbladders and demonstrated bacterial antigens staining (granular and filamentous patterns) around blood vessels of the serosa and muscle layer. Rare intact bacteria were seen in 1 case. These results show that leptospirosis can mimic the clinical symptoms of acute cholecystitis. If a cholecystectomy is performed in febrile patients with suspicious environmental or animal exposure, pathologic studies for leptospirosis on formalin-fixed, paraffin-embedded tissues may be of great value.

Molecular and conventional epidemiology of Mycobacterium tuberculosis in Botswana: a population-based prospective study of 301 pulmonary tuberculosis patients

Little is known about patterns of tuberculosis (TB) transmission among populations in developing countries with high rates of TB and human immunodeficiency virus (HIV) infection. To examine patterns of TB transmission in such a setting, we performed a population-based DNA fingerprinting study among TB patients in Botswana. Between January 1997 and July 1998, TB patients from four communities in Botswana were interviewed and offered HIV testing. Their Mycobacterium tuberculosis isolates underwent DNA fingerprinting using IS6110 restriction fragment length polymorphism, and those with matching fingerprints were reinterviewed. DNA fingerprints with >5 bands were considered clustered if they were either identical or differed by at most one band, while DNA fingerprints with < or =5 bands were considered clustered only if they were identical. TB isolates of 125 (42%) of the 301 patients with completed interviews and DNA fingerprints fell into 20 different clusters of 2 to 16 patients. HIV status was not associated with clustering. Prior imprisonment was the only statistically significant risk factor for clustering (risk ratio, 1.5; 95% confidence interval, 1.1 to 2.0). In three communities where the majority of eligible patients were enrolled, 26 (11%) of 243 patients overall and 26 (25%) of 104 clustered patients shared both a DNA fingerprint and strong antecedent epidemiologic link. Most of the increasing TB burden in Botswana may be attributable to reactivation of latent infection, but steps should be taken to control ongoing transmission in congregate settings. DNA fingerprinting helps determine loci of TB transmission in the community.

Meningococcal vaccines

Global control and prevention of meningococcal disease depends on the further development of vaccines that overcome the limitations of the current polysaccharide vaccines. Protein-polysaccharide conjugate vaccines likely will address the marginal protective antibody responses and short duration of immunity in young children derived from the A, C, Y, and W-135 capsular polysaccharides, but they will be expensive to produce and purchase, and may not offer a practical solution to the countries with greatest need. In addition, OMP vaccines have been tested extensively in humans and hold some promise in the development of a serogroup B vaccine, but are limited by the antigenic variability of these subcapsular antigens and the resulting strain-specific protection. Elimination of meningococcal disease likely will require a novel approach to vaccine development, ideally incorporating a safe and effective antigen or antigens common to all meningoccocal serogroups. As a solely human pathogen, however, N. meningitidis has developed many tools with which to evade the human immune system, and likely will pose a formidable challenge for years to come.

Genetic and immunologic characterization of a novel serotype 4, 15 strain of Neisseria meningitidis

The porin proteins of Neisseria meningitidis are important components of outer membrane protein (OMP) vaccines. The class 3 porin gene, porB, of a novel serogroup B, serotype 4, 15 isolate from Chile (Ch501) was found to be VR1-4, VR2-15, VR3-15 and VR4-15 by porB variable region (VR) typing. Rabbit immunization studies using outer membrane vesicles revealed immunodominance of individual PorB (class 3) VR epitopes. The predominant anti-Ch501 PorB response was directed to the VR1 epitope. Anti-PorB VR1 mediated killing was suggested by the bactericidal activity of Ch501 anti-sera against a type 4 strain not expressing PorA or class 5 OMPs. Studies that examine the molecular epidemiology of individual porB VRs, and the immune responses to PorB epitopes, may contribute to the development of broadly protective group B meningococcal vaccines.

Completeness and timeliness of treatment initiation after laboratory diagnosis of tuberculosis in Gaborone, Botswana

SETTING

Gaborone, the capital of Botswana.

OBJECTIVE

To determine the time from positive sputum smear microscopy for acid-fast bacilli (AFB) to initiation of therapy, and to identify risk factors for delays.

DESIGN

Retrospective cohort study of medical records and surveillance data for patients with positive smear microscopy and newly diagnosed tuberculosis (TB) from January to May 1997. Treatment delay was defined as more than 2 weeks from the first positive sputum smear to the initiation of TB treatment.

RESULTS

Of 127 patients identified, 15 (11.8%) had treatment delay, 13 (10.2%) had an incomplete workup (only one smear performed) and were not registered for TB treatment, and six (4.5%) had two or more positive smears but were not registered for TB treatment. Risk factors for treatment delay or non-registration included TB patients who had been diagnosed in a hospital outpatient setting vs. a clinic (RR 2.9, 95% CI 1.2-3.6, P = 0.02), or in a high volume vs. low volume clinic (RR 2.2, 95% CI 1.2-5.3, P = 0.01).

CONCLUSION

More than a quarter of the smear-positive TB patients identified had treatment delay or no evidence of treatment initiation. Proper monitoring of laboratory sputum results and suspect TB patient registers could potentially reduce treatment delays and patient loss.

DNA fingerprinting of a national sample of Mycobacterium tuberculosis isolates, Botswana, 1995-1996

DNA fingerprinting may be useful to elucidate tuberculosis (TB) transmission in community settings, but its utility is limited if only few fingerprint patterns are observed or band numbers are low. We performed DNA fingerprinting on a national, population-based sample of Mycobacterium tuberculosis isolates from Botswana. During 1995-1996, a random sample of 213 isolates, representing 5% of all smear-positive TB cases, underwent DNA fingerprinting using restriction fragment length polymorphism (RFLP) IS6110 analysis. Eighty-two (38%) of the 213 isolates belonged to one of 18 clusters, with 2-9 isolates/cluster. The median number of bands was 10 (range 1-19); 183 (86%) had six or more bands. Sixty-three (49%) of 128 patients tested were infected with the human immunodeficiency virus (HIV). The degree of RFLP pattern heterogeneity and high band number support the feasibility of a prospective DNA fingerprinting study in Botswana.

Survey of drug resistance of Mycobacterium tuberculosis in 3 Mexican states, 1997

BACKGROUND

Drug resistance threatens global tuberculosis (TB) control efforts. Population-based estimates of drug resistance are needed to develop strategies for controlling drug-resistant TB in Mexico.

OBJECTIVE

To obtain population-based data on Mycobacterium tuberculosis drug resistance in Mexico.

METHODS

To obtain drug resistance data, we conducted a population-based study of TB cases in the states of Baja California, Sinaloa, and Oaxaca, Mexico. We performed cultures and drug susceptibility testing on M tuberculosis isolates from patients with newly diagnosed, smear-positive TB from April 1 to October 31, 1997.

RESULTS

Mycobacterium tuberculosis was isolated from 460 (75%) of the 614 patients. Levels of resistance in new and retreatment TB cases to 1 or more of the 3 current first-line drugs used in Mexico (isoniazid, rifampin, and pyrazinamide) were 12.9% and 50.5%, respectively; the corresponding levels of multi-drug-resistant TB were 2.4% and 22.4%. Retreatment cases were significantly more likely than new cases to have isolates resistant to 1 or more of the 3 first-line drugs (relative risk [RR], 3.9; 95% confidence interval [CI], 2.8-5.5), to have isoniazid resistance (RR, 3.6; 95% CI, 2.5-5.2), and to have multi-drug-resistant TB (RR, 9.4; 95% CI, 4.3-20.2).

CONCLUSIONS

This population-based study of M tuberculosis demonstrates moderately high levels of drug resistance. Important issues to consider in the national strategy to prevent M tuberculosis resistance in Mexico include consideration of the most appropriate initial therapy in patients with TB, the treatment of patients with multiple drug resistance, and surveillance or periodic surveys of resistance among new TB patients to monitor drug resistance trends.

Analysis of the 1998 outbreak of leptospirosis in Missouri in humans exposed to infected swine

OBJECTIVE

To determine the extent of leptospirosis in persons exposed to infected swine, confirm the source of disease, define risk factors for infection, and identify means for preventing additional infections during an outbreak in Missouri in 1998.

DESIGN

Cross-sectional study.

SAMPLE POPULATION

240 people and 1,700 pigs.

PROCEDURE

An epidemiologic investigation was conducted of people exposed to infected pigs from the University of Missouri-Columbia swine herd. The investigation included review of health of the pigs, a cross-sectional study of the people handling the pigs, serologic testing of human and porcine sera, and risk-factor analysis for leptospirosis within the human population.

RESULTS

Serologic testing of samples collected at the time of the investigation indicated that 59% of the pigs had titers to leptospires, denoting exposure. Of the 240 people in the exposed study population, 163 (68%) were interviewed, and of these, 110 (67%) submitted a blood sample. Nine (8%) cases of leptospirosis were confirmed by serologic testing. Risk factors associated with leptospirosis included smoking (odds ratio [OR], 14.4; 95% confidence interval [CI], 1.39 to 137.74) and drinking beverages (OR, 5.1; 95% CI, 1.04 to 24.30) while working with infected pigs. Washing hands after work was protective (OR, 0.2; 95% CI, 0.03 to 0.81).

CONCLUSIONS AND CLINICAL RELEVANCE

Leptospirosis is a risk for swine producers and slaughterhouse workers, and may be prevented through appropriate hygiene, sanitation, and animal husbandry. It is essential to educate people working with animals or animal tissues about measures for reducing the risk of exposure to zoonotic pathogens.

Mycobacterium ulcerans infection

After tuberculosis and leprosy, Buruli-ulcer disease (caused by infection with Mycobacterium ulcerans) is the third most common mycobacterial disease in immunocompetent people. Countries in which the disease is endemic have been identified, predominantly in areas of tropical rain forest; the emergence of Buruli-ulcer disease in West African countries over the past decade has been dramatic. Current evidence suggests that the infection is transmitted through abraded skin or mild traumatic injuries after contact with contaminated water, soil, or vegetation; there is one unconfirmed preliminary report on possible transmission by insects. The clinical picture ranges from a painless nodule to large, undermined ulcerative lesions that heal spontaneously but slowly. Most patients are children. The disease is accompanied by remarkably few systemic symptoms, but occasionally secondary infections resulting in sepsis or tetanus cause severe systemic disease and death. Extensive scarring can lead to contractures of the limbs, blindness, and other adverse sequelae, which impose a substantial health and economic burden. Treatment is still primarily surgical, and includes excision, skin grafting, or both. Although BCG has a mild but significant protective effect, new vaccine developments directed at the toxins produced by M. ulcerans are warranted. In West Africa, affected populations are underprivileged, and the economic burden imposed by Buruli-ulcer disease is daunting. Combined efforts to improve treatment, prevention, control, and research strategies (overseen by the WHO and funded by international relief agencies) are urgently needed.

Immunogenicity of 2 serogroup B outer-membrane protein meningococcal vaccines: a randomized controlled trial in Chile

CONTEXT

Meningococcal disease occurs worldwide, and serogroup B disease accounts for a large proportion of cases. Although persons younger than 4 years are at greatest risk for serogroup B meningococcal disease, vaccine efficacy has not been demonstrated in this age group.

OBJECTIVE

To evaluate serum bactericidal activity (SBA) against homologous vaccine type strains and a heterologous Chilean epidemic strain of Neisseria meningitidis as a potential correlate for vaccine efficacy.

DESIGN

Double-blind, randomized controlled trial conducted between March 14 and July 20, 1994. All blood samples were taken by December 1994.

SETTING

Santiago, Chile, where a clonal serogroup B meningococcal disease epidemic began in 1993.

PARTICIPANTS

Infants younger than 1 year (n = 187), children aged 2 to 4 years (n = 183), and adults aged 17 to 30 years (n = 173).

INTERVENTION

Participants received 3 doses of outer-membrane protein (OMP) meningococcal vaccine developed in either Cuba or Norway or a control vaccine, with each dose given 2 months apart. Blood samples were obtained at baseline, prior to dose 3, and at 4 to 6 weeks after dose 3.

MAIN OUTCOME MEASURE

Immune response, defined as a 4-fold or greater rise in SBA titer 4 to 6 weeks after dose 3 compared with prevaccination titer.

RESULTS

Children and adult recipients of either meningococcal vaccine were more likely than controls to develop an immune response to the heterologous epidemic strain. After 3 doses of vaccine, 31% to 35% of children responded to the vaccine vs 5% to placebo; 37% to 60% of adults responded to vaccine vs 4% to placebo (P<.05 vs control for all). Infants, however, did not respond. In contrast, against homologous vaccine type strains, the response rate was 67% or higher among children and adults and 90% or higher among infants (P<.001 vs control for all). Subsequent SBA against 7 isogenic homologous target strains identified class 1 OMP as the immunodominant antigen.

CONCLUSIONS

These data suggest that neither serogroup B OMP meningococcal vaccine would confer protection during a heterologous epidemic. However, epidemic strain-specific vaccines homologous for class 1 OMP are promising candidates for the control of epidemic serogroup B meningococcal disease.

Tuberculin reactivity in a pediatric population with high BCG vaccination coverage

SETTING

The tuberculin skin test (TST) is often included in diagnostic algorithms for tuberculosis (TB) in children. TST interpretation, however, may be complicated by prior Bacillus Calmette-Guerin (BCG) vaccination. We assessed the prevalence of and risk factors for positive TST reactions in children 3 to 60 months of age in Botswana, a country with high TB rates and BCG coverage of over 90%.

METHODS

A multi-stage cluster survey was conducted in one rural and three urban districts. Data collected included demographic characteristics, nutritional indices, vaccination status, and prior TB exposure. Mantoux TSTs were administered and induration measured at 48-72 hours.

RESULTS

Of 821 children identified, 783 had TSTs placed and read. Of the 759 children with vaccination cards, 755 (99.5%) had received BCG vaccine. Seventy-nine per cent of children had 0 mm induration, 7% had > or =10 mm induration ('positive' TST), and 2% had > or =15 mm. A positive TST was associated with reported contact with any person with active TB (odds ratio [OR] 1.9; 95% confidence interval [CI] 1.02-3.6), or a mother (OR 5.1; 95% CI 2.1-12.4) or aunt (OR 5.3; 95% CI 2.0-14.0) with active TB. TSTs > or =5 mm (but not > or =10 mm) were associated with presence of a BCG scar. Positive reactions were not associated with age, time since BCG vaccination, clinical signs or symptoms of TB, nutritional status, crowding, or recent measles or polio immunization.

CONCLUSION

The TST remains useful in identifying children with tuberculous infection in this setting of high TB prevalence and extensive BCG coverage.

Age-dependent Neisseria meningitidis serogroup C class-specific antibody concentrations and bactericidal titers in sera from young children from Montana immunized with a licensed polysaccharide vaccine

Neisseria meningitidis serogroup C bactericidal titers and class-specific enzyme-linked immunosorbent assay (ELISA) antibody concentrations were measured in sera from 173 children (1 to 5 years old) before and 6 weeks and 7 months following vaccination with a quadrivalent (A/C/Y/W-135) polysaccharide vaccine. The immune responses of the children were compared with those of 40 adults 6 weeks postvaccination. Both bactericidal titers and ELISA antibody concentrations were significantly higher in the adults than in the children (P < 0.05). In addition, the ratio of immunoglobulin G (IgG) to IgM was higher in the children than in the adults. With an ELISA total antibody concentration of >/=2 microg/ml used as a measure of seroconversion, >/=84% of the individuals from each age group responded to the serogroup C polysaccharide. However, with a >/=4-fold-increase in bactericidal titer used, only 18% of 1-year-olds, 32% of 2-year-olds, and 50 to 60% of 3-, 4-, and 5-year-olds seroconverted. The ELISA results suggest that >50% of all children retained >/=2 microg of total antibody per ml at 7 months postimmunization. However, the bactericidal titers suggest that <10% of children <4 years old retained a >/=4-fold increase at 7 months following vaccination. Of particular note, 59 of 79 sera (75%) from the 1- and 2-year-olds had high ELISA antibody concentrations (2 to 20 microg/ml) with no associated bactericidal titer (<1:8). Discordant results between bactericidal titers and ELISA antibody concentrations were not explained by the presence of IgA blocking antibody or relative levels of IgG and IgM. The bactericidal results show age-dependent differences in the production and retention of antibody in young children immunized with serogroup C polysaccharide; these differences are not evident with the ELISA data.

Molecular epidemiology of bartonella infections in patients with bacillary angiomatosis-peliosis

BACKGROUND

Bacillary angiomatosis and bacillary peliosis are vascular proliferative manifestations of infection with species of the genus bartonella that occur predominantly in patients infected with the human immunodeficiency virus. Two species, B. henselae and B. quintana, have been associated with bacillary angiomatosis, but culture and speciation are difficult, and there has been little systematic evaluation of the species-specific disease characteristics. We studied 49 patients seen over eight years who were infected with bartonella species identified by molecular techniques and who had clinical lesions consistent with bacillary angiomatosis-peliosis.

METHODS

In this case-control study, a standardized questionnaire about exposures was administered to patients with bacillary angiomatosis-peliosis and to 96 matched controls. The infecting bartonella species were determined by molecular techniques.

RESULTS

Of the 49 patients with bacillary angiomatosis-peliosis, 26 (53 percent) were infected with B. henselae and 23 (47 percent) with B. quintana. Subcutaneous and lytic bone lesions were strongly associated with B. quintana, whereas peliosis hepatis was associated exclusively with B. henselae. Patients with B. henselae infection were identified throughout the study period and were epidemiologically linked to cat and flea exposure (P< or =0.004), whereas those with B. quintana were clustered and were characterized by low income (P=0.003), homelessness (P = 0.004), and exposure to lice (P= 0.03). Prior treatment with macrolide antibiotics appeared to be protective against infection with either species.

CONCLUSIONS

B. henselae and B. quintana, the organisms that cause bacillary angiomatosis-peliosis, are associated with different epidemiologic risk factors and with predilections for involvement of different organs.

Research issues involving HIV-associated tuberculosis in resource-poor countries

Each year, there are an estimated 8 million new cases of tuberculosis (TB) and 3 million deaths due to TB, most of which occur in resource-poor countries. Tuberculosis incidence is increasing rapidly in countries with high rates of human immunodeficiency virus (HIV) infection, and despite the availability of effective interventions, many TB programs are failing to cope with the increased TB caseload. This report highlights gaps in current understanding of the interaction between TB and HIV that contribute to failure of optimal TB management and control; we focus on the diagnosis of TB, its epidemiology and transmission, preventive strategies, and programmatic issues in the integration of HIV and TB services. Research into how best to apply existing knowledge will be at least as important as searching for new knowledge. The global control of TB will also require increased resources, greater political commitment, and stronger international public health leadership.

Meningococcal disease in Los Angeles County, California, and among men in the county jails

BACKGROUND

From January through March 1993, there were 54 cases of meningococcal disease in Los Angeles County, California, of which 9 occurred among men incarcerated in the county's jail system, which was 40 percent above capacity at the time. Several of the 45 patients from the community had had contact with men recently released from a county jail.

METHODS

We interviewed patients from the community (n=42) and neighborhood controls matched with the patients for age, race, and ethnic group (n=84) about potential exposures. We collected and cultured pharyngeal swabs for Neisseria meningitidis from men entering the central jail (n=162), men leaving the central jail (n=379), members of the jail staff (n=121), and patients at a community health center (n=214). Meningococcal isolates were identified by serotyping and multilocus enzyme electrophoresis.

RESULTS

The presence of community-acquired meningococcal disease was strongly associated with exposure to a person who had been in or worked at one of the county jails (multivariate matched odds ratio, 18.5; 95 percent confidence interval, 3.8 to 90.8; P<0.001). Pharyngeal carriage of meningococcus was significantly more frequent among men released from jail (19 percent) or entering jail (17 percent) than among workers at the jails (3 percent) or community residents seen at the clinic (1 percent). Among men entering jail, those who had previously been incarcerated were more often carriers than those who had not (21 percent vs. 7 percent, P=0.03). Of the isolates from nine community residents with serogroup C meningococcal disease, eight were the same strain as that isolated from the eight inmates with serogroup C disease.

CONCLUSIONS

In this outbreak of meningococcal disease in Los Angeles County, nearly half of community residents with the disease had contact with persons who had been in a county jail. The high rates of carriage among recidivists and released inmates suggests that the men became meningococcal carriers while in jail.

Bacillary angiomatosis and bacillary peliosis in patients infected with human immunodeficiency virus: clinical characteristics in a case-control study

Clinical characteristics associated with bacillary angiomatosis and bacillary peliosis (BAP) in patients with human immunodeficiency virus (HIV) infection were evaluated in a case-control study; 42 case-patients and 84 controls were matched by clinical care institution. Case-patients presented with fever (temperature, > 37.8 degrees C; 93%), a median CD4 lymphocyte count of 21/mm3, cutaneous or subcutaneous vascular lesions (55%), lymphadenopathy (21%), and/or abdominal symptoms (24%). Many case-patients experienced long delays between medical evaluation and diagnosis of BAP (median, 4 weeks; range, 1 day to 24 months). Case-patients were more likely than controls to have fever, lymphadenopathy, hepatomegaly, splenomegaly, a low CD4 lymphocyte count, anemia, or an elevated serum level of alkaline phosphatase (AP) (P < .001). In multivariate analysis, a CD4 lymphocyte count of < 200/mm3 (matched odds ratio [OR], 9.9; P < .09), anemia reflected by a hematocrit value of < 0.36 (OR, 19.7; P < .04), and an elevated AP level of > or = 2.6 mukat/L (OR, 23.9; P < .05) remained associated with disease after therapy with zidovudine was controlled for. BAP should be considered an AIDS-defining opportunistic infection and should be included in the differential diagnosis for febrile, HIV-infected patients with cutaneous or osteolytic lesions, lymphadenopathy, abdominal symptoms, anemia, or an elevated serum level of AP.

Utility of emergency, telephone-based national surveillance for Hantavirus pulmonary syndrome. Hantavirus Task Force

On May 27, 1993, in response to the outbreak investigation of newly recognized Hantavirus pulmonary syndrome (HPS) in the Four Corners states (New Mexico, Arizona, Utah, and Colorado), the Centers for Disease Control and Prevention established a national surveillance case definition for severe, unexplained respiratory disease to determine the extent of HPS throughout the United States. A toll-free telephone hotline number was instituted to provide updated information about unexplained respiratory illness and to serve as a passive mechanism for reporting suspected cases. Clinical information was obtained from callers reporting suspected cases, and diagnostic specimens and medical record reviews were requested from health care providers. From June 3 through December 31, 1993, the hotline received 21,443 telephone inquiries; callers identified 280 suspected cases living outside the Four Corners states with at least one specimen available for diagnostic testing. By December 31, 1993, 21 confirmed cases (age range, 14 to 58 years) residing in 11 states outside the Four Corners region had been identified. This passive surveillance system was successful in rapidly identifying the widespread sporadic geographic distribution for HPS cases throughout the United States and could serve as a model for similar emergencies. Expanding and coordinating surveillance systems for the early detection, tracking, and evaluation of emerging infections is a critical component of disease prevention.

Cutaneous manifestations of opportunistic infections in patients infected with human immunodeficiency virus

Bacillary angiomatosis (BA) presents most commonly as a cutaneous disease and is caused by two organisms. Bartonella (Rochalimaea) henselae and Bartonella (Rochalimaea) quintana. Biopsy confirmation of cutaneous BA is essential because lesions can mimic nodular Kaposi's sarcoma in appearance. Although the vast majority of human immunodeficiency virus (HIV)-infected patients with BA have CD4 lymphocyte counts of less than 100 cells per mm3, the disease responds well to antimicrobial therapy. Staphylococcus aureus is the most common bacterial skin pathogen affecting HIV-infected patients. The prevalence of skin disease due to S. aureus may be explained by high nasal carriage rates for the organism ( > or = 50%) and altered immune function in conjunction with an impaired cutaneous barrier. Herpes simplex virus causes mucocutaneous disease early in the course HIV infection and ulcerative lesions at any site in advanced HIV infection. Herpes zoster is common early in the course of HIV infection; recurrent and disseminated herpes zoster infections are characteristic of patients with advanced HIV disease. Acyclovir resistance is usually seen in patients with large, untreated, ulcerative lesions of herpes simplex virus and in patients with chronic, verrucous lesions of varicella-zoster virus. Cutaneous cryptococcosis, histoplasmosis, and coccidiomycosis are markers of disseminated disease and require biopsy confirmation. Scabies is easily diagnosed but may be atypical in presentation and difficult to eradicate in advanced HIV disease.

Reduction in the incidence of human listeriosis in the United States. Effectiveness of prevention efforts? The Listeriosis Study Group

BACKGROUND

Food-borne transmission is now recognized as a major cause of human listeriosis.

OBJECTIVE

To assess the impact of prevention efforts, listeriosis rates before interventions were initiated in 1989 were compared with more recent rates (1990 through 1993).

DESIGN

From 1989 through 1993, multistate, laboratory-based active surveillance was conducted to identify all cases in which Listeria monocytogenes was isolated from cultures or ordinarily sterile sites in an aggregate population of more than 19 million.

SETTING

All laboratories serving acute care hospitals in up to nine surveillance areas in the United States.

INTERVENTIONS

In 1989, a well-publicized case report of listeriosis linked to processed poultry led US regulatory agencies to enforce aggressive food monitoring policies and prompted industry to invest in cleanup efforts. In May 1992, consumer guidelines for listeriosis prevention were disseminated.

OUTCOME MEASURES

Cases of perinatal and nonperinatal listeriosis.

RESULTS

The rate of listeriosis decreased in all surveillance areas. Projection of these rates to the US population suggests an estimated 1965 cases and 481 deaths occurred in 1989 compared with an estimated 1092 cases and 248 deaths in 1993, a 44% and 48% reduction in illness and death, respectively. Among adults 50 years of age and older, rates declined from 16.2 per 1 million in 1989 to 10.2 per 1 million in 1993 (P = .02). Perinatal disease decreased from 17.4 cases per 100,000 births in 1989 to 8.6 cases per 100,000 births in 1993 (P = .003). Three serotypes (1/2a, 1/2b, and 4b) of L monocytogenes accounted for more than 96% of cases during each year of the study (1989 through 1993).

CONCLUSIONS

The incidence of listeriosis in study areas was substantially lower in 1993 than in 1989. The temporal association of this reduction with industry, regulatory, and educational efforts suggests these measures were effective.

Hantavirus pulmonary syndrome in California: report of two cases and investigation

We report two cases of hantavirus pulmonary syndrome that were probably acquired in California. Genetic analysis of tissue specimens from one of the patients revealed that the virus isolated is a variant of the strain (Sin Nombre virus) identified in the outbreak of hantavirus pulmonary syndrome that occurred in the Four Corners region of the southwestern United States in 1993. In addition to presenting the clinical features of the two cases, we discuss the possible risk factors for infection.

Rochalimaea henselae infection. A new zoonosis with the domestic cat as reservoir

OBJECTIVE

To determine the reservoir and vector(s) for Rochalimaea henselae, a causative agent of bacillary angiomatosis (BA) and cat scratch disease, and to estimate the percentage of domestic cats with R henselae bacteremia in the Greater San Francisco Bay Region of Northern California.

DESIGN

Hospital-based survey of patients diagnosed with BA who also had significant exposure to at least one pet cat, as well as a convenience sampling of pet or impounded cats for prevalence of Rochalimaea bacteremia.

SETTING

Community and university hospitals and clinics; veterinary clinics treating privately owned or impounded cats.

PATIENTS

Patients with or without human immunodeficiency virus infection, with biopsy-confirmed BA, who had prolonged exposure to pet cats prior to developing BA.

MAIN OUTCOME MEASURES

Cultures and laboratory studies were performed on blood drawn from pet cats associated with patients with BA. The Rochalimaea species infecting pet cats and fleas and causing the BA lesions in human contacts of these cats was identified by culture, polymerase chain reaction-restriction fragment length polymorphism analysis, and DNA sequencing. The presence of R henselae bacteremia in pet cats was documented, and predictor variables for culture positivity were evaluated.

RESULTS

Four patients diagnosed with BA who had prolonged contact with seven pet cats were identified. The Rochalimaea species causing BA lesions in these patients was determined to be R henselae. The seven pet cats were found to be bacteremic with R henselae; this bacterium was also detected in fleas taken from an infected cat by both direct culture and polymerase chain reaction. Blood samples were cultured from pet and impounded cats (N = 61) in the Greater San Francisco Bay Region, and R henselae was isolated from 41% (25/61) of these cats.

CONCLUSION

We have documented that the domestic cat serves as a major persistent reservoir for R henselae, with prolonged, asymptomatic bacteremia from which humans, especially the immunocompromised, may acquire potentially serious infections. Antibiotic treatment of infected cats and control of flea infestation are potential strategies for decreasing human exposure to R henselae.

Kaposi's sarcoma. Epidemiology, pathogenesis, histology, clinical spectrum, staging criteria and therapy

The acquired immunodeficiency syndrome (AIDS) epidemic has had a profound impact on our understanding of Kaposi's sarcoma (KS). Epidemiologic features suggest a sexually transmitted cofactor in the pathogenesis of AIDS-associated KS (AIDS-KS), and several putative agents have received intense scrutiny. Cell culture studies suggest that the angiogenesis of AIDS-KS is stimulated by both human immunodeficiency virus proteins and growth factors that may be involved in the development and progression of AIDS-KS, thereby providing a rationale for new therapeutic interventions. The dermatologist is uniquely qualified to provide care for the majority of patients with KS, as many patients have cutaneous lesions amendable to local therapy (cryotherapy, intralesional therapy, simple excision). Patients requiring more aggressive local therapy (radiation therapy) or systemic therapies (interferon, chemotherapy) can be easily recognized. Standardized staging criteria provide assistance for determining appropriate local or systemic therapy and for evaluating and comparing responses to new therapies. This article reviews the epidemiology, pathogenesis, histologic features, clinical spectrum, staging criteria, and treatment of KS.

The epidemiology of bacillary angiomatosis and bacillary peliosis

OBJECTIVE

To determine environmental risk factors for bacillary angiomatosis-bacillary peliosis (BAP), and to confirm infection with Rochalimaea species.

DESIGN

Case-control study.

SETTING

Community and university hospitals and clinics.

PATIENTS

Case patients (N = 48) had biopsy-confirmed BAP. Controls (N = 94) were matched to patients by institution and by human immunodeficiency virus (HIV) serological status.

MAIN OUTCOME MEASURES

Clinical information was obtained from medical records. Subjects were queried about environmental exposures. Univariate odds ratios (ORs) with 95% confidence intervals (CIs) were determined. Bivariate analyses were performed on variables associated with disease by univariate analysis. DNA from 22 available case-patient tissues and from 22 control tissues was amplified with the polymerase chain reaction (PCR) using primers designed to detect Rochalimaea species.

RESULTS

We identified five HIV-negative, immunocompetent case patients; one HIV-negative, immunodeficient case patient; and 42 HIV-positive case patients. There were no significant differences between case patients and controls by race, sex, age, or risk factors for HIV infection. Owning a cat (OR, 2.8; CI, 1.4 to 5.8) and history of a recent cat lick (OR, 1.95; CI, 1.0 to 3.8), cat scratch (OR, 3.7; CI, 1.7 to 8.0), or cat bite (OR, 3.9; CI, 1.8 to 8.9) were associated with disease in the univariate analysis. In bivariate analyses, only the variables representing traumatic contact with a cat (bite or scratch) remained associated with disease. No other environmental exposure was associated with disease. The PCR amplified a DNA fragment of the size expected for Rochalimaea species in all 22 case-patient tissue specimens.

CONCLUSIONS

These data suggest that BAP is a new zoonosis associated with both traumatic exposure to cats and infection with Rochalimaea species or a closely related organism.

The epidemiology of bacillary angiomatosis and bacillary peliosis

OBJECTIVE

To determine environmental risk factors for bacillary angiomatosis-bacillary peliosis (BAP), and to confirm infection with Rochalimaea species.

DESIGN

Case-control study.

SETTING

Community and university hospitals and clinics.

PATIENTS

Case patients (N = 48) had biopsy-confirmed BAP. Controls (N = 94) were matched to patients by institution and by human immunodeficiency virus (HIV) serological status.

MAIN OUTCOME MEASURES

Clinical information was obtained from medical records. Subjects were queried about environmental exposures. Univariate odds ratios (ORs) with 95% confidence intervals (CIs) were determined. Bivariate analyses were performed on variables associated with disease by univariate analysis. DNA from 22 available case-patient tissues and from 22 control tissues was amplified with the polymerase chain reaction (PCR) using primers designed to detect Rochalimaea species.

RESULTS

We identified five HIV-negative, immunocompetent case patients; one HIV-negative, immunodeficient case patient; and 42 HIV-positive case patients. There were no significant differences between case patients and controls by race, sex, age, or risk factors for HIV infection. Owning a cat (OR, 2.8; CI, 1.4 to 5.8) and history of a recent cat lick (OR, 1.95; CI, 1.0 to 3.8), cat scratch (OR, 3.7; CI, 1.7 to 8.0), or cat bite (OR, 3.9; CI, 1.8 to 8.9) were associated with disease in the univariate analysis. In bivariate analyses, only the variables representing traumatic contact with a cat (bite or scratch) remained associated with disease. No other environmental exposure was associated with disease. The PCR amplified a DNA fragment of the size expected for Rochalimaea species in all 22 case-patient tissue specimens.

CONCLUSIONS

These data suggest that BAP is a new zoonosis associated with both traumatic exposure to cats and infection with Rochalimaea species or a closely related organism.

Intralesional vinblastine for cutaneous Kaposi's sarcoma associated with acquired immunodeficiency syndrome. A clinical trial to evaluate efficacy and discomfort associated with infection

BACKGROUND

Intralesional vinblastine has been used to treat Kaposi's sarcoma associated with acquired immunodeficiency syndrome (AIDS-KS). Injections are painful and anticipated response rates are not well documented.

OBJECTIVE

Eleven homosexual men were studied to evaluate the efficacy and pain associated with intralesional vinblastine with or without 1% bicarbonate buffered lidocaine (BBL).

METHODS

Six lesions on each patient were selected and treated with either vinblastine, vinblastine mixed with BBL, or vinblastine 5 minutes after BBL injection. Control lesions received BBL, saline, or no treatment. Patients recorded injection pain on a visual analog scale.

RESULTS

There was a complete or partial clinical response in 88% of vinblastine-treated lesions. Pain scores for BBL, vinblastine, and the mixture of BBL and vinblastine were not statistically different.

CONCLUSION

Intralesional vinblastine is effective therapy for AIDS-KS. Local anesthesia does not reduce efficacy of treatment, or reduce the pain experienced by the patient.

Isolation of Rochalimaea species from cutaneous and osseous lesions of bacillary angiomatosis

BACKGROUND

Bacillary angiomatosis is characterized by vascular lesions, which occur usually in patients infected with the human immunodeficiency virus (HIV). A newly described gram-negative organism, Rochalimaea henselae, has been associated with cutaneous bacillary angiomatosis, but no organism has been isolated and cultivated directly from cutaneous tissue.

METHODS

We used two methods to isolate the infecting bacterium from four HIV-infected patients with cutaneous lesions suggestive of bacillary angiomatosis: cultivation with eukaryotic tissue-culture monolayers and direct plating of homogenized tissue onto agar. The patients' blood was cultured with the lysis-centrifugation method. Isolates recovered from skin and blood were identified by sequencing all or part of the 16S ribosomal RNA gene amplified with the polymerase chain reaction.

RESULTS

R. quintana, historically known as the agent of trench fever, was isolated from cutaneous lesions in three patients, after tissue homogenates were cultivated with endothelial-cell monolayers; R. henselae was isolated from a cutaneous lesion in one patient. In two patients, R. quintana was isolated from both cutaneous tissue and blood; in one patient it was also isolated from bone.

CONCLUSIONS

In bacillary angiomatosis, either of two species of rochalimaea--R. quintana or R. henselae--can be isolated from cutaneous lesions or blood, providing an additional method of diagnosis.

Pulsed-dye laser therapy for cutaneous Kaposi's sarcoma associated with acquired immunodeficiency syndrome

BACKGROUND

Cutaneous lesions of Kaposi's sarcoma associated with acquired immunodeficiency syndrome (AIDS-KS) are disfiguring.

OBJECTIVE

This study assesses the response of AIDS-KS to pulsed-dye laser (PDL) therapy.

METHODS

The PDL was used to treat 15 AIDS-KS patients. Treatment was repeated at 4-week intervals. On average, patients received three treatments per treated lesion.

RESULTS

At 6 weeks' follow-up, the patients' treated lesions were reduced in size when compared with their matched control lesions (p less than 0.002). A complete or partial clinical response occurred in 44% of treated lesions (17 of 39) compared with 18% of matched control lesions (7 of 39) [corrected]. Patients experienced limited pain, infrequent blistering, and no scarring. However, histopathologic findings of treated lesions throughout therapy correlated poorly with clinical response. At 12 weeks, all treated lesions had recurred.

CONCLUSION

PDL therapy for AIDS-KS is not recommended. Although safe, the rapid recurrence of disease at initially responsive sites would require costly, long-term therapy to maintain cosmetic improvement.

Bacillary (epithelioid) angiomatosis and concurrent Kaposi's sarcoma in acquired immunodeficiency syndrome

Two patients with acquired immunodeficiency syndrome developed simultaneous Kaposi's sarcoma and bacillary (epithelioid) angiomatosis. The distinguishing clinical and histologic features of these two vascular proliferations associated with human immunodeficiency virus disease are described. The lesions of bacillary (epithelioid) angiomatosis contained bacteria, while the lesions of Kaposi's sarcoma did not. With erythromycin therapy, the lesions of bacillary (epithelioid) angiomatosis cleared, while those of Kaposi's persisted. Bacillary (epithelioid) angiomatosis, a treatable but potentially fatal opportunistic infection of human immunodeficiency virus disease, should be considered in the differential diagnosis of vascular lesions in immunosuppressed patients.