Severe gastritis in the Peruvian Andes.

OBJECTIVE: To compare the Helicobacter pylori-associated pathology in gastric biopsies taken from patients living at sea level with those taken from patients living at high altitude. METHODS AND RESULTS: We included 38 patients from a hospital in the Andean city of La Oroya, Peru, located at 3700 m in altitude, and 40 control patients taken from Comas Clinic located in the city of Lima at sea level. Fibrepanendoscopy and multiple biopsies were performed in all the patients followed by histopathological examination. In the antrum, patients from the Andean town had a higher prevalence of glandular lymphoid adherence lesions, active germinal centres, moderate to severe chronic atrophic gastritis, intestinal metaplasia and moderate to severe total deep gland loss, than did patients from the coastal town. Furthermore, the severity of the histological lesions seen in the gastric body and cardia was significantly greater in the high-altitude patients than in those from sea level. CONCLUSION: This study suggests that the severity of H. pylori-associated gastric lesions seen on histopathological examination is greater in patients living at high altitude, the cause of which is most probably multifactorial but nonetheless principally altitude related.

E-mail surveys assist investigation and response: a university conjunctivitis outbreak.

A conjunctivitis outbreak affecting more than 200 individuals occurred on a university campus in Evanston, Illinois, USA, in spring 2002. An investigation was conducted jointly by the Evanston Department of Health and the Illinois Department of Public Health. A combination of e-mail and traditional telephone-based surveys demonstrated that wearing contact lenses was a risk factor for any conjunctivitis and bilateral conjunctivitis, whereas using glasses was protective. Laboratory and epidemiological evidence suggested that the outbreak was caused by a viral pathogen that eluded characterization despite extensive culture and PCR-based laboratory testing. Enhanced laboratory surveillance could help clinicians and public-health officials to identify relevant secular changes in the spectrum of causes of conjunctivitis. During institutional outbreaks, e-mail surveys can help public-health officials to efficiently access information not easily collected by traditional case-control studies, and can provide an effective conduit for providing prevention recommendation, such as the need for improved hand and contact-lens hygiene during outbreaks.

No association between Helicobacter pylori and Mycobacterium tuberculosis infections among gastrointestinal clinic attendees in Lima, Peru.

Helicobacter pylori (HP) infection can cause hypochlorhydria, a positive risk factor for Mycobacterium tuberculosis (MTB) infection. This study examined the association between HP and MTB infections among persons attending the Policlinico Peruano Japonés Gastrointestinal Clinic in Lima, Peru. From 23 June 2000 to 18 August 2000, consenting 18-55 year olds who attended the clinic for gastric biopsy gave blood for HP serologic testing, underwent tuberculin skin testing (TST) and completed a social and medical history. Of 128 participating patients, 78 (61%) were TST positive for MTB, and 107 (84%) were infected with HP by serology. Of the patients who were HP positive, 67 (63%) developed positive TST reactions compared to 11 (52%) of 21 HP-seronegative subjects (OR 1.29; 95% CI 0.54-3.11; P = 0.6). There was no association after adjusting for covariates of H. pylori infection (OR 0.78; 95% CI 0.23-2.71; P = 0.7). However, study power was limited by high prevalence of the two infections.

A modification of the quininium resin test for assessing gastric acidity.

BACKGROUND: Gastric acid is an important defence against enteric infection. Studies investigating the relationship between hypochlorhydria and enteric infections or gastric malignancy have been limited by difficulties in the non-invasive measurement of gastric acidity. AIM: To develop a blood test for hypochlorhydria based on the quininium resin test. METHODS: Quininium resin dissociates to liberate free quinine at pH

Invasive group A streptococcal infections in the San Francisco Bay area, 1989-99.

To describe the epidemiology of invasive group A streptococcal (iGAS) infections in the San Francisco Bay Area, population-based active surveillance for laboratory-confirmed iGAS was conducted by the California Emerging Infections Program in three California counties. From January 1989 to December 1999, 1415 cases of iGAS were identified. Mean iGAS incidence was 4.06/100,000 person-years and case fatality ratio was 13%, with no linear trends over time. Incidence was lowest in adolescents, was higher in men than women (4.4 vs. 3.2/100,000 person-years), and was higher in African-Americans (6.7) than in non-Hispanic (4.1) or Hispanic (3.4) Whites, Asians (2.2) or Native Americans (17/100,000 person-years). Injecting drug use was the riskiest underlying condition and was associated with the highest attributable risk. Cases were associated with several underlying conditions, but 23% occurred in previously healthy persons. From 1989-1999, iGAS infections in the San Francisco Bay Area became neither more common nor more deadly.

Acute Helicobacter pylori infection is followed by an increase in diarrheal disease among Peruvian children.

BACKGROUND: Cohort and case-crossover studies were conducted to evaluate whether new Helicobacter pylori infections are followed by increased diarrhea. METHODS: Participants were 6-month-old to 12-year-old shantytown residents living near Lima, Peru. Baseline data were collected from community households. Health interviews were completed daily, and sera, drawn every 4 months, were tested for H pylori immunoglobulin G. Diarrhea rates among newly H pylori-infected (seroconverting) children were compared with rates among persistently uninfected and infected children using cohort and case-crossover analyses. RESULTS: Sera were obtained from 345 children from January 1, 1995, through September 1, 1997. H pylori incidence was 12% per year (36 H pylori infections in 109 866 seronegative days). In adjusted cohort analyses, seroconverters had more diarrhea days (rate ratio: 2.0; 95% confidence interval: 1.6-2.4), episodes, and sick days in the year after infection than did uninfected children; and more diarrhea days and sick days than did persistently infected children. This effect was strongest in the first 2 months. Case-crossover analyses supported these findings. CONCLUSION: Preventing H pylori infection may help reduce pediatric diarrheal disease.

Adenovirus type 3 viremia in an adult with toxic shock-like syndrome.

Surveillance by the Unexplained Deaths and Critical Illnesses Project (UNEX) uncovered a novel presentation of adenovirus type 3 infection that satisfied the criteria for toxic shock-like syndrome in a 28-year-old immunocompetent man. Adenovirus may be a cause of toxic shock syndrome; surveillance systems such as UNEX may uncover additional causes of this and other clinically defined infectious syndromes.

Predominant kidney involvement in a fatal case of hantavirus pulmonary syndrome caused by Sin Nombre virus.

A 27-year-old woman presented to a hospital with symptoms resembling pyelonephritis; respiratory distress did not develop until nearly a day after admission and she subsequently died. The Unexplained Deaths and Critical Illnesses Project of the Centers for Disease Control and Prevention confirmed Sin Nombre virus infection by the results of serological testing and sequencing of the viral genome; staining of Sin Nombre virus antigen in the pulmonary capillaries was relatively weak.

Fecal leukocyte stain has diagnostic value for outpatients but not inpatients.

The methylene blue stain for fecal leukocytes (FL) is widely used as an adjunct to slower but more accurate tests of diarrheal etiology, such as stool culture (SCx) or toxin assays for Clostridium difficile. Prior studies investigating the utility of FL for predicting SCx and C. difficile toxin assay (CDTA) results did not evaluate the importance of inpatient versus outpatient status. We conducted a study of patients who submitted a stool specimen to the Stanford Hospital Microbiology Laboratory between May 1998 and April 1999. The results for stool specimens that were tested by FL and by a confirmatory test (either SCx or CDTA) were used to determine whether the FL method helped to predict the results of these tests. Of 797 stools that were tested by FL method and at least one confirmatory test, 502 stools were tested by CDTA, and 473 stools were cultured. The FL test was 14% sensitive and 90% specific for C. difficile with a diagnostic threshold of one white blood cell/high-power field (WBC/HPF). The overall likelihood ratio (LR) for a positive CDTA was 1.4 with a 95% confidence interval (CI) of 0. 5 to 3.7 (P = 0.5) and was similar among inpatients and outpatients. In contrast, the presence of >/=1 WBC/HPF was 52% sensitive and 88% specific for the 27 positive SCx results and helped to predict a positive SCx result (LR, 4.2; 95% CI, 2.7 to 6.5; P < 0.001). The sensitivity of >/=1 WBC/HPF was 57%, and its predictive value for SCx was higher among outpatients (outpatient LR, 5.0; 95% CI, 2.9 to 8.6; P < 0.001; inpatient LR, 1.9; 95% CI, 0.3 to 10.8; P = 0.5). Among inpatients, only 4 (1.5%) of the 273 SCx results were positive, and the presence of >/=1 WBC/HPF was insensitive (25%) and did not predict a positive SCx (LR, 1.9; 95% CI, 0.3 to 10.8; P = 0.5). When the data were reanalyzed using a diagnostic threshold of five WBC/HPF for FL, the predictive power of the FL method was similar. Thus, FL was of no value in predicting CDTA positivity, nor was it helpful in predicting SCx results for inpatients. Neither SCx nor the FL method should routinely be performed on samples from inpatients. Among outpatients, presence of FLs should suggest a bacterial diarrhea in clinically compatible cases.

Efavirenz- and adefovir dipivoxil-based salvage therapy in highly treatment-experienced patients: clinical and genotypic predictors of virologic response.

OBJECTIVE: To determine the impact of prior nonnucleoside reverse transcriptase inhibitor (NNRTI) therapy, genotypic resistance, and other variables on response to efavirenz (EFV)- and adefovir dipivoxil (ADV)-based salvage therapy. DESIGN: Retrospective clinical cohort study. SETTING: One university and one community-based HIV clinic. STUDY SUBJECTS: All 33 patients who were coenrolled in both the EFV and ADV expanded access programs. INTERVENTIONS: Patients received EFV 600 mg/day and ADV 120 mg/day in addition to other antiretroviral agents. OUTCOME MEASURE: HIV viral load (<500 copies/ml) at 12 and 24 weeks. RESULTS: 10 of 33 (30%) patients at 12 weeks and 8 of 33 (24%) patients at 24 weeks had viral loads <500 copies/ml. Prior NNRTI use and a history of any NNRTI-associated mutations predicted failure. Patients with Y181C or G190A single mutations had an initial greater magnitude of viral load suppression than those with K103N, but this advantage was short lived. No one with any NNRTI mutations responded with a viral load <500 copies/ml at 12 or 24 weeks. CONCLUSIONS: EFV/ADV-based salvage yielded viral load suppression at 24 weeks in 42% (8 of 19) of patients who were highly NRTI and protease inhibitor experienced but NNRTI naive. NNRTI-experienced study subjects had a poor response regardless of the specific NNRTI resistance mutation they harbored.

Helicobacter pylori and epidemic Vibrio cholerae O1 infection in Peru.

In a cross-sectional study of the 1991 Peruvian cholera epidemic, Vibrio cholerae O1 infection was associated with Helicobacter pylori infection, particularly in young children. These data support the hypothesis that hypochlorhydria induced by H. pylori is important in the pathogenesis of diarrhoeal disease.

Wound botulism associated with black tar heroin among injecting drug users.

CONTEXT: Wound botulism (WB) is a potentially lethal, descending, flaccid, paralysis that results when spores of Clostridium botulinum germinate in a wound and elaborate neurotoxin. Since 1988, California has experienced a dramatic increase in WB associated with injecting "black tar" heroin (BTH), a dark, tarry form of the drug. OBJECTIVE: To identify risk factors for WB among injecting drug users (IDUs). DESIGN: Case-control study based on data from in-person and telephone interviews. PARTICIPANTS: Case patients (n=26) were IDUs who developed WB from January 1994 through February 1996. Controls (n=110) were IDUs newly enrolled in methadone detoxification programs in 4 counties. MAIN OUTCOME MEASURES: Factors associated with the development of WB. RESULTS: Among the 26 patients, the median age was 41.5 years, 15 (58%) were women, 14 (54%) were non-Hispanic white, 11 (42%) were Hispanic, and none were positive for the human immunodeficiency virus. Nearly all participants (96% of patients and 97% of controls) injected BTH, and the mean cumulative dose of BTH used per month was similar for patients and controls (27 g and 31 g, respectively; P=.6). Patients were more likely than controls to inject drugs subcutaneously or intramuscularly (92% vs 44%, P<.001) and used this route of drug administration more times per month (mean, 67 vs 24, P<.001), with a greater cumulative monthly dose of BTH (22.3 g vs 6.3 g, P<.001). A dose-response relationship was observed between the monthly cumulative dose of BTH injected subcutaneously or intramuscularly and the development of WB (chi2 for linear trend, 26.5; P<.001). In the final regression model, subcutaneous or intramuscular injection of BTH was the only behavior associated with WB among IDUs (odds ratio, 13.7; 95% confidence interval, 3.0-63.0). The risk for development of WB was not affected by cleaning the skin, cleaning injection paraphernalia, or sharing needles. CONCLUSIONS: Injection of BTH intramuscularly or subcutaneously is the primary risk factor for the development of WB. Physicians in the western United States, where BTH is widely used, should be aware of the potential for WB to occur among IDUs.

Postoperative Serratia marcescens wound infections traced to an out-of-hospital source.

From 25 August to 28 September 1994, 7 cardiovascular surgery (CVS) patients at a California hospital acquired postoperative Serratia marcescens infections, and 1 died. To identify the outbreak source, a cohort study was done of all 55 adults who underwent CVS at the hospital during the outbreak. Specimens from the hospital environment and from hands of selected staff were cultured. S. marcescens isolates were compared using restriction-endonuclease analysis and pulsed-field gel electrophoresis. Several risk factors for S. marcescens infection were identified, but hospital and hand cultures were negative. In October, a patient exposed to scrub nurse A (who wore artificial fingernails) and to another nurse-but not to other identified risk factors-became infected with the outbreak strain. Subsequent cultures from nurse A's home identified the strain in a jar of exfoliant cream. Removal of the cream ended the outbreak. S. marcescens does not normally colonize human skin, but artificial nails may have facilitated transmission via nurse A's hands.

Epidemic Salmonella enteritidis infection in Los Angeles County, California. The predominance of phage type 4.

Between April and July 1994, 501 cases of Salmonella enteritidis infection were reported in Los Angeles County, California, nearly 5 times the number reported between April and July 1993; of these, 422 (84%) were sporadic (not related to known outbreaks). A case-control study was done to determine risk factors for sporadic illness; the distribution of S enteritidis phage types was evaluated. Case-patients (n = 58) were county residents older than 1 year with culture-confirmed S enteritidis infection in August 1994. One to two acquaintance controls (n = 98) were matched to each case by age, sex, and race. Two risk factors-eating raw or undercooked eggs (matched odds ratio [MOR] = 6.6; 95% confidence interval [CI] = 1.9, 23.0) and eating in restaurants (MOR = 4.9; 95% CI = 1.2, 19.4) in the 3 days before the onset of illness-remained significant in the conditional logistic regression model. Of 16 randomly selected S enteritidis case-isolates, 15 (94%) were phage type 4. The reasons for the regional predominance of phage type 4, an S enteritidis subtype recently associated with large and destructive increases in salmonellosis among poultry and humans in Britain and much of Europe, are unclear. To minimize human S enteritidis infection, food service workers need frequent training in the proper handling of raw foods, eggs should be kept refrigerated during distribution and storage, and eggs should be cooked until the yolk is firm, particularly for persons at the greatest risk for serious illness: pregnant women, elderly persons, and those with compromised immune systems. Clinicians should obtain stool specimens for culture from patients who present with diarrhea and fever or bloody diarrhea or who are possibly part of an outbreak.