Alejandro Bussalleu

Validation of String Test for Diagnosis of Helicobacter pylori Infections

ABSTRACT The method of recovering Helicobacter pylori DNA or viable cells absorbed on a string that a person has swallowed and that is retrieved an hour later (string test) should be a useful alternative to traditional analysis of cells or DNA obtained by endoscopy, which is invasive, uncomfortable, relatively costly, and ill-suited for community-based and pediatric studies. Here we assayed the sensitivity and validity of the string test versus conventional endoscopic biopsy for detecting and analyzing H. pylori infection. Forty-four people with gastric complaints were studied using both H. pylori culture and urease gene (ureB) PCR. H. pylori organisms cultured from strings and biopsy specimens from the same patients were fingerprinted by the randomly amplified polymorphic DNA (RAPD) method. Biopsy sections were also hematoxylin and eosin and silver stained for H. pylori detection. H. pylori was cultured from 80% of strings and detected by PCR from 91% of strings from participants whose biopsies had been H. pylori positive by culture, PCR, and/or histology. Strains recovered from strings and biopsy specimens yielded identical or closely related RAPD profiles in each of the 24 cases tested. We conclude that the string test is a useful method for H. pylori recovery and analysis when relatively noninvasive procedures are needed.

Variation in the prevalence of gastric cancer in Perú

Most cases of gastric cancers occur in non‐industrialized countries but there is scarce information about the epidemiology of this illness in these countries. Our study examined whether there was a variation in the prevalence of gastric cancer in Lima, Perú over the last 2 decades. Subjects older than 29 years of age were included. They underwent an esophagogastroduedonoscopy at 3 socioeconomically different health facilities in Lima: a county hospital (7,168 subjects), a Peruvian‐Japanese Clinic (14,794 individuals) and a private hospital (4,893 individuals). Birth cohort prevalence of gastric cancer was used. Regression models were calculated to predict the future prevalence of gastric cancer. It was found that the birth cohort prevalence of gastric cancer decreased in Perú from 22.7 to 2% (p < 0.001), from 12 to 0.5% (p < 0.001), and from 6.5 to 0.1% (p < 0.001) in the low, middle and high socioeconomic group, respectively. The prevalence of intestinal metaplasia decreased from 44.3 to 12.5% (p < 0.001), from 28.4 to 5% (p < 0.001), and from 19.4 to 2.2% (p < 0.001) in the low, middle and high socioeconomic status, respectively. These trends will likely persist over the future decades. Nevertheless, the prevalence of gastric cancer remains high in subjects older than 59 years of age in the low socioeconomic status. It is concluded that the prevalence of gastric cancer is decreasing in Perú, similar to the current trend undergoing in industrialized nations. However, there are still specific groups with high prevalence that might benefit from screening for early detection and treatment.

Giant gastroduodenal trichobezoar: Rapunzel syndrome.

To the Editor: Bezoars are non-digestible material collections located inside the gastrointestinal tract. Th e most common are phytobezoars that are of vegetable origin. Trichobezoars are caused due to ingestion of hair associated with trichotillomania. Rapunzel syndrome is characterized by a gastric trichobezoar in which the mass goes through the pylorus extending into the small bowel and sometimes even to the colon (1,2) . A 16-year-old girl came to our outpatient clinic complaining of intermittent colicky abdominal pain located at the epigastrium accompanied by nausea and vomiting. Th ese symptoms were worsening and she had also lost her appetite and had started to lose weight as the nausea and vomiting persisted. She lost 24 kg in a year. She recalled having a craving for dirt (pica) when she was 11 years old. She was married to a much older man (more than twice her age). Her examination showed a thin girl with pallor and swollen red nail beds with no bitten nails. Th ere were no areas of alopecia on her head. In the upper abdomen, we were able to feel a nontender 5 × 10 cm hard mass with regular borders that could be moved a little. On laboratory examination, we found mild anemia (hemoglobin 11 g / dl) and severe hypoalbuminemia (1.7 g / dl). A simple abdominal X-ray showed gastric distension. We performed an upper gastroduodenal endoscopy and were able to identify an extensive mass of hair, wool, and vegetables that covered the entire stomach and duodenum to as far as we could scope ( Figure 1 ). Th e patient was transferred to the surgical ward where a laparotomy was performed, extracting a giant trichobezoar that was 120 cm long ( Figure 2 ). She had an uneventful recovery and was able to start eating again without nausea or vomiting. When evaluated by the psychiatrist, she was diagnosed with major depression and discharged with medication aft er 72 h. Trichobezoars are frequent in young women usually with a psychiatric disorder. Rapunzel syndrome has been named aft er the heroine of a German fairy tale by the Grimm Brothers. Rapunzel let her long golden hair down the tower where she was imprisoned, to allow her prince lover to climb up and rescue her (3) . Th e fi rst Rapunzel syndrome case was described by Vaughan in 1968; it is quite uncommon as there are only 33 cases reported worldwide, one of them previously in Peru (4) . Th ey are formed because of the voluntary ingestion of indigestible material. Most patients present with gastrointestinal symptoms, mainly abdominal pain, distension, nausea, vomiting, or early satiety. Diagnosis is usually carried out by endoscopy and the extraction is by open surgery, although there have been some reports with laparoscopy (5) . An adequate psychiatric assessment is important to avoid its recurrence.

Antibiotic resistance among Helicobacter pylori clinical isolates in Lima, Peru

Objectives Gastric carcinoma is the most common cancer and cause of cancer mortality in Peru. Helicobacter pylori, a bacterium that colonizes the human stomach, is a Group 1 carcinogen due to its causal relationship to gastric carcinoma. While eradication of H. pylori can help prevent gastric cancer, characterizing regional antibiotic resistance patterns is necessary to determine targeted treatment for each region. Thus, we examined primary antibiotic resistance in clinical isolates of H. pylori in Lima, Peru. Materials and methods H. pylori strains were isolated from gastric biopsies of patients with histologically proven H. pylori infection. Primary antibiotic resistance among isolates was examined using E-test strips. Isolates were examined for the presence of the cagA pathogenicity island and the vacA m1/m2 alleles via polymerase chain reaction. Results Seventy-six isolates were recovered from gastric biopsies. Clinical isolates showed evidence of antibiotic resistance to 1 (27.6%, n=21/76), 2 (28.9%, n=22/76), or ≥3 antibiotics (40.8%). Of 76 isolates, eight (10.5%) were resistant to amoxicillin and clarithromycin, which are part of the standard triple therapy for H. pylori infection. No trends were seen between the presence of cagA, vacA m1, or vacA m2 and antibiotic resistance. Conclusion The rate of antibiotic resistance among H. pylori isolates in Lima, Peru, is higher than expected and presents cause for concern. To develop more targeted eradication therapies for H. pylori in Peru, more research is needed to better characterize antibiotic resistance among a larger number of clinical isolates prospectively.

Tuberculin skin test conversion among health sciences students: A retrospective cohort study

Previous studies have reported that health sciences students are at greater risk for tuberculosis infection, especially in developing countries. The objective of this study was to estimate the prevalence, incidence, and factors associated with latent tuberculosis infection among Health Sciences students in Peru. Students enrolled at private university (in Lima-Peru) are tested annually for tuberculosis infection by tuberculin skin test. Data on tuberculin skin test results between 2002 and 2009 was used in this retrospective cohort study, a total of 4842 students were included. Tuberculin skin test conversion was defined as the change of tuberculin skin test from negative (<10 mm) to positive (≥10 mm) after 48-72 h of inoculation. Baseline tuberculin skin test positivity was 1.0% (95%CI: 0.6%-1.3%), whereas tuberculin skin test conversion incidence was 12.4 per 100 person-years (95%CI: 11.8-13.0). This study showed that students from clinical careers in close contact with patients had an increased risk of tuberculosis infection in the internship, especially Medicine, Dentistry, Medical Technology and Nursing. Administrative, environmental and personal protection measures should be implemented and evaluated periodically in order to reduce the risk of exposure.

An assessment of drinking water contamination with Helicobacter pylori in Lima, Peru

Helicobacter pylori is a gut bacterium that is the primary cause of gastric cancer. H. pylori infection has been consistently associated with lack of access to sanitation and clean drinking water. In this study, we conducted time‐series sampling of drinking water in Lima, Peru, to examine trends of H. pylori contamination and other water characteristics.

Hepatitis inespecífica asociada a otra patología

En la practica medica es frecuente encontrar patologia extrahepatica a la que se asocian manifestaciones de hepatitis que ha recibido diferentes denominaciones, siendo la mas usual hepatitis reactiva o reaccional inespecifica, que no obstante no es aceptada por todos. Como ejemplo se presentan 20 casos atendidos en el Hospital Cayetano Heredia, senalandose los hallazgos clinicos, de laboratorio y anatomo-patologicos. Se establece que en el cuadro clinico predomina la enfermedad de fondo, presentandose en algun momeno fiebre, coluria, ictericia y hepatomegalia ligeramente dolorosa. Se encuentra hiperbilirrubinemia que no excede de 3 a 4 mg/dl a predominio de la conjugada; elevacion de las transaminasas que no suelen pasar de 250-300 UI/dl y fosfatasa alcalina elevada en 2 a 3 veces lo normal. La biopsia hepatica realizada en todos los casos esta caracterizada por cambios inflamatorios inespecificos: injuria o necrosis focal leve, infiltracion celular de tipo portal y en alguna dilatacion sinusoidal o cambios minimos a nivel de los colangiolos. Se plantea que las alteraciones se producen por la susceptibilidad hepatica a un conjunto de posibles factores toxicos, metabolicos, circulatorios, inmunologicos y otros aun no conocidos. El pronostico y tratamiento se relacionan con la enfermedad de fondo, evitando los hepatotoxicos.

Unique Clinical Problems in Latin America

Common gastrointestinal (GI) diseases affecting AIDS patients have been described in other chapters of this volume. The objective of this chapter is to include some clinical forms of the disease involving GI problems that have been seen in Latin America during the AIDS pandemic.

Helicobacter pylori eradication with tetracycline, furazolidone and bismuth (TFB), and rate of reinfection one year after successful treatment

H. pylori (HP) is a prevalent infection in Peru. High rates of resistance against some antibiotics as well as elevated costs affect the effectiveness of some therapies.