Helicobacter pylori infection: A balance between bacteria and host / Helicobacter pylori: un balance entre bacterias y huésped

Abstract In Argentina, despite the important studies conducted on the prevalence of infection and the antibiotic resistance of Helicobacter pylori, there are no reports simultaneously analyzing a profile of virulence factors of the bacterium and polymorphisms in cytokine genes in patients with different alterations in the gastric mucosa (including intestinal metaplasia, IM). Our aim was to evaluate H. pylori genotypes in 132 adult patients with chronic gastritis presenting three different histological findings (inactive chronic gastritis, active chronic gastritis IM( and active chronic gastritis IM+) along with SNP-174 G>C in the IL-6 gene. cagA, vacA and babA2 genes were analyzed by multiplex PCR. The -174 G>C SNP IL-6 gene was analyzed by PCR-RFLP. Patients with active chronic gastritis IM+ showed the highest proportion of the cagA(+)/IL-6GG, cagA(+)/vacAm1s1/IL-6GG and cagA(+)/vacAm1s1/babA2(+)/IL-6GG combinations (p<0.05). There was 4-5 times greater probability of finding patients presenting the GG genotype for SNP-174 G>C IL-6, which in turn were infected with the most virulent H. pylori genotypes -cagA(+), cagA(+)/vacAm1s1 and cagA(+)/vacAm1s1/babA2- in the ACGIM+ group in comparison to the ICG group. Our results provide regional data to the idea that the transition towards severe alterations in the gastric mucosa would be the result of a balance between specific factors of H. pylori and inherent host factors. This fact can be useful to identify patients at greater risk and to select those individuals requiring appropriate eradication treatment to prevent progression to gastric cancer.

Resumen En Argentina, a pesar de los importantes estudios realizados sobre la prevalencia de infección y la resistencia a antibióticos de Helicobacter pylori, no existen reportes que analicen simultáneamente un perfil de factores de virulencia de la bacteria y polimorfismos en genes de citoquinas en pacientes con diferentes alteraciones en la mucosa gástrica (incluida la metaplasia intestinal [MI]). Nuestro objetivo fue evaluar genotipos de H. pylori en 132 pacientes adultos con gastritis crónica, con tres diferentes hallazgos histológicos (gastritis crónica inactiva [GCI], gastritis crónica activa [MI(] y gastritis crónica activa [MI+]), junto con el SNP-174 G>C en el gen de IL- 6. Los genes cagA, vacA y babA2 se analizaron mediante PCR multiplex. El SNP-174 G>C IL-6 se analizó mediante PCR-RFLP. Los pacientes con gastritis crónica activa MI+ mostraron la mayor proporción de combinaciones cagA(+)/IL-6GG, cagA(+)/vacAm1s1/IL-6GG y cagA(+)/vacAm1s1/babA2(+)/IL-6GG (p<0,05). Hubo 4-5 veces mayor probabilidad de encontrar pacientes con el genotipo GG en SNP-174 G>C IL-6 y a su vez infectados con los genotipos más virulentos de H. pylori-cagA(+), cagA(+)/vacAm1s1 y cagA(+)/vacAm1s1/babA2-en el grupo gastritis crónica activa MI+ en comparación con el grupo GCI. Nuestros resultados aportan datos regionales a la idea de que la transición hacia alteraciones más graves en la mucosa gástrica resultaría de un equilibrio entre factores específicos de H. pylori y factores inherentes al huésped. Esto puede ser útil para identificar pacientes con mayor riesgo y seleccionar aquellos individuos que requieran un apropiado tratamiento de erradicación para prevenir la progresión al cáncer gástrico.

Helicobacter pylori infection: A balance between bacteria and host.

In Argentina, despite the important studies conducted on the prevalence of infection and the antibiotic resistance of Helicobacter pylori, there are no reports simultaneously analyzing a profile of virulence factors of the bacterium and polymorphisms in cytokine genes in patients with different alterations in the gastric mucosa (including intestinal metaplasia, IM). Our aim was to evaluate H. pylori genotypes in 132 adult patients with chronic gastritis presenting three different histological findings (inactive chronic gastritis, active chronic gastritis IM- and active chronic gastritis IM+) along with SNP-174 G>C in the IL-6 gene. cagA, vacA and babA2 genes were analyzed by multiplex PCR. The -174 G>C SNP IL-6 gene was analyzed by PCR-RFLP. Patients with active chronic gastritis IM+ showed the highest proportion of the cagA(+)/IL-6GG, cagA(+)/vacAm1s1/IL-6GG and cagA(+)/vacAm1s1/babA2(+)/IL-6GG combinations (p<0.05). There was 4-5 times greater probability of finding patients presenting the GG genotype for SNP-174 G>C IL-6, which in turn were infected with the most virulent H. pylori genotypes -cagA(+), cagA(+)/vacAm1s1 and cagA(+)/vacAm1s1/babA2- in the ACGIM+ group in comparison to the ICG group. Our results provide regional data to the idea that the transition towards severe alterations in the gastric mucosa would be the result of a balance between specific factors of H. pylori and inherent host factors. This fact can be useful to identify patients at greater risk and to select those individuals requiring appropriate eradication treatment to prevent progression to gastric cancer.

Usefulness of rapid urease test samples for molecular analysis of clarithromycin resistance in Helicobacter pylori / Utilidad de las muestras de test rápido de ureasa para el análisis molecular de resistencia a claritromicina en Helicobacter pylori

Helicobacter pylori is a gastric pathogen that is widely recognized as a causative agent of gastric disease. Its eradication is variable, mainly due to increased resistance to clarithromycin. Our objective was: to evaluate (i) if the biopsy specimen used for the rapid urease test is a useful sample to detect resistance to clarithromycin by PCR-RFLP and (ii) the distribution of A2142G and A2143G point mutations in the 23S rRNA gene, in relation to virulence factors in our region. Gastric specimens were collected from adult dyspeptic patients (n = 141) and H. pylori was investigated by the rapid urease test, histopathological analysis and PCR for the hsp60 gene. Clarithromycin resistance was detected by PCR-RFLP in 62 H. pylori (+) paired biopsy specimens submitted to molecular analysis and the rapid urease test. H. pylori virulence factors were analyzed by multiplex PCR using specific primers for the cagA, vacA and babA2 genes. Thirteen out of 62 strains (20.9%) were resistant to clarithromycin: 6/13 (46.2%) harbored the A2143G mutation whereas 7/13 (53.8%) carried the A2142G point mutation. vacA m1s1 was the most frequent genotype among the resistant strains. In conclusion, the biopsy specimens used for the rapid urease test were suitable samples for clarithromycin resistance detection in patients infected with H. pylori, which became especially useful in cases where the number or size of the biopsies is limited. In addition, this is the first report of a molecular analysis for clarithromycin resistance performed directly from gastric biopsies in our region.

Helicobacter pylori es un patógeno ampliamente reconocido como causante de enfermedad gástrica. Su erradicación es variable, principalmente debido al incremento de la resistencia a claritromicina. Nuestros objetivos fueron evaluar la utilidad de la biopsia usada para realizar el test rápido de ureasa en la detección de resistencia a claritromicina por PCR-RFLP y conocer la distribución de las mutaciones puntuales A2142G y A2143G en el gen ARNr 23S, en relación con los factores de virulencia en nuestra región. Se recolectaron muestras gástricas (n=141) provenientes de pacientes adultos dispépticos y se investigó la presencia de H. pylori mediante el test rápido de ureasa, análisis histopatológico y PCR para el gen hsp60. La resistencia a claritromicina se analizó por PCR-RFLP en 62 muestras pareadas de biopsias gástricas H. pylori+ destinadas al análisis molecular y al test rápido de ureasa. Los factores de virulencia de H. pylori fueron analizados mediante PCR multiplex usando oligonucleótidos específicos para los genes cagA, vacA y babA2. Trece de 62 cepas (20,9%) fueron resistentes a claritromicina, 6/13 (46,2%) llevaron la mutación A2143G, mientras que 7/13 (53,8%) presentaron la mutación A2142G. El genotipo vacA s1m1 fue el más frecuente entre las cepas resistentes a claritromicina. En conclusión, las biopsias destinadas al test rápido de ureasa fueron muestras apropiadas para la detección de la resistencia a claritromicina en pacientes infectados con H. pylori. Esto es especialmente útil en aquellos casos en los que el número o el tamaño de las muestras son limitados. Además, este es el primer reporte de estudio de resistencia a claritromicina (mediante técnicas moleculares), directamente de biopsias gástricas en nuestra región.

Usefulness of rapid urease test samples for molecular analysis of clarithromycin resistance in Helicobacter pylori.

Helicobacter pylori is a gastric pathogen that is widely recognized as a causative agent of gastric disease. Its eradication is variable, mainly due to increased resistance to clarithromycin. Our objective was: to evaluate (i) if the biopsy specimen used for the rapid urease test is a useful sample to detect resistance to clarithromycin by PCR-RFLP and (ii) the distribution of A2142G and A2143G point mutations in the 23S rRNA gene, in relation to virulence factors in our region. Gastric specimens were collected from adult dyspeptic patients (n=141) and H. pylori was investigated by the rapid urease test, histopathological analysis and PCR for the hsp60 gene. Clarithromycin resistance was detected by PCR-RFLP in 62 H. pylori (+) paired biopsy specimens submitted to molecular analysis and the rapid urease test. H. pylori virulence factors were analyzed by multiplex PCR using specific primers for the cagA, vacA and babA2 genes. Thirteen out of 62 strains (20.9%) were resistant to clarithromycin: 6/13 (46.2%) harbored the A2143G mutation whereas 7/13 (53.8%) carried the A2142G point mutation. vacA m1s1 was the most frequent genotype among the resistant strains. In conclusion, the biopsy specimens used for the rapid urease test were suitable samples for clarithromycin resistance detection in patients infected with H. pylori, which became especially useful in cases where the number or size of the biopsies is limited. In addition, this is the first report of a molecular analysis for clarithromycin resistance performed directly from gastric biopsies in our region.

[Esophageal papilloma: case report, molecular identification of human papillomavirus and literature review]. / Papiloma esofágico: descripción de un caso, identificación molecular del virus del papiloma humano y revisión de la literatura.

sophageal squamous papilloma is an uncommon, usually asymptomatic, benign tumor of the squamous epithelium consisting of a raised, sessile, small and round (smooth or rough) lesion. The prevalence is between 0.01 and 0.45% of cases, with a male/female ratio of 3:1. The etiology and pathogenesis appear to be a mechanical or chemical irritation of the mucosa in addition to the presence of human papillomavirus (HPV), important agent in the evolution to a squamous carcinoma, especially HPV types 16 and 18. In this paper, we describe a case of esophageal papilloma whose diagnosis involved endoscopic images, pathological studies and detection of viral DNA by polymerase chain reaction. By using molecular techniques (PCR-RFLP) a profile consistent with HPV type 16 has been obtained. The patient underwent polypectomy and currently, after 3 years of diagnosis, he remains asymptomatic. This work is one of the first national reports of a patient with esophageal papilloma in which one of the most frequently HPV genotypes associated with esophageal carcinoma (HPV 16) has been detected.

[Molecular detection and genotypification of Helicobacter pylori in gastric biopsies from symptomatic adult patients in Santa Fe, Argentina]. / Detección molecular y genotipificación de Helicobacter pylori en biopsias gástricas de pacientes adultos sintomáticos de la ciudad de Santa Fe, Argentina.

Our goals were: a) to detect Helicobacter pylori in gastric biopsies of symptomatic adults by PCR, b) to detect the presence of the cagA gene as well as of the allelic variants of the vacA gene, and c) to correlate genotypes with the endoscopic diagnoses. H. pylori was detected in 81 % (39/48) of patients by nested PCR for hsp60. The presence of cagA was detected in 15/22 of samples and vacA s1 - m1 was the most frequent allelic combination (15/22). Gastritis, the most frequent diagnosis, was associated with genotype cagA+ in 10/13 of patients. In this group, 9/13 showed the allelic variant vacA s1- m1. The variant vacA s2 - m2 was detected in 3/3 of gastritis cases by H. pylori with the cagA- genotype. These results are the first reported in our region and provide data of epidemiological interest.

Detección molecular y genotipificación de Helicobacter pylori en biopsias gástricas de pacientes adultos sintomáticos de la ciudad de Santa Fe, Argentina / [Molecular detection and genotypification of Helicobacter pylori in gastric biopsies from symptomatic adult patients in Santa Fe, Argentina].

Our goals were: a) to detect Helicobacter pylori in gastric biopsies of symptomatic adults by PCR, b) to detect the presence of the cagA gene as well as of the allelic variants of the vacA gene, and c) to correlate genotypes with the endoscopic diagnoses. H. pylori was detected in 81

(39/48) of patients by nested PCR for hsp60. The presence of cagA was detected in 15/22 of samples and vacA s1 - m1 was the most frequent allelic combination (15/22). Gastritis, the most frequent diagnosis, was associated with genotype cagA+ in 10/13 of patients. In this group, 9/13 showed the allelic variant vacA s1- m1. The variant vacA s2 - m2 was detected in 3/3 of gastritis cases by H. pylori with the cagA- genotype. These results are the first reported in our region and provide data of epidemiological interest.

Papiloma esofágico: descripción de un caso, identificación molecular del virus del papiloma humano y revisión de la literatura / [Esophageal papilloma: case report, molecular identification of human papillomavirus and literature review].

sophageal squamous papilloma is an uncommon, usually asymptomatic, benign tumor of the squamous epithelium consisting of a raised, sessile, small and round (smooth or rough) lesion. The prevalence is between 0.01 and 0.45

of cases, with a male/female ratio of 3:1. The etiology and pathogenesis appear to be a mechanical or chemical irritation of the mucosa in addition to the presence of human papillomavirus (HPV), important agent in the evolution to a squamous carcinoma, especially HPV types 16 and 18. In this paper, we describe a case of esophageal papilloma whose diagnosis involved endoscopic images, pathological studies and detection of viral DNA by polymerase chain reaction. By using molecular techniques (PCR-RFLP) a profile consistent with HPV type 16 has been obtained. The patient underwent polypectomy and currently, after 3 years of diagnosis, he remains asymptomatic. This work is one of the first national reports of a patient with esophageal papilloma in which one of the most frequently HPV genotypes associated with esophageal carcinoma (HPV 16) has been detected.

Papiloma esofágico: descripción de un caso, identificación molecular del virus del papiloma humano y revisión de la literatura. / [Esophageal papilloma: case report, molecular identification of human papillomavirus and literature review].

sophageal squamous papilloma is an uncommon, usually asymptomatic, benign tumor of the squamous epithelium consisting of a raised, sessile, small and round (smooth or rough) lesion. The prevalence is between 0.01 and 0.45

of cases, with a male/female ratio of 3:1. The etiology and pathogenesis appear to be a mechanical or chemical irritation of the mucosa in addition to the presence of human papillomavirus (HPV), important agent in the evolution to a squamous carcinoma, especially HPV types 16 and 18. In this paper, we describe a case of esophageal papilloma whose diagnosis involved endoscopic images, pathological studies and detection of viral DNA by polymerase chain reaction. By using molecular techniques (PCR-RFLP) a profile consistent with HPV type 16 has been obtained. The patient underwent polypectomy and currently, after 3 years of diagnosis, he remains asymptomatic. This work is one of the first national reports of a patient with esophageal papilloma in which one of the most frequently HPV genotypes associated with esophageal carcinoma (HPV 16) has been detected.

Detección molecular y genotipificación de Helicobacter pylori en biopsias gástricas de pacientes adultos sintomáticos de la ciudad de Santa Fe, Argentina. / [Molecular detection and genotypification of Helicobacter pylori in gastric biopsies from symptomatic adult patients in Santa Fe, Argentina].

Our goals were: a) to detect Helicobacter pylori in gastric biopsies of symptomatic adults by PCR, b) to detect the presence of the cagA gene as well as of the allelic variants of the vacA gene, and c) to correlate genotypes with the endoscopic diagnoses. H. pylori was detected in 81

(39/48) of patients by nested PCR for hsp60. The presence of cagA was detected in 15/22 of samples and vacA s1 - m1 was the most frequent allelic combination (15/22). Gastritis, the most frequent diagnosis, was associated with genotype cagA+ in 10/13 of patients. In this group, 9/13 showed the allelic variant vacA s1- m1. The variant vacA s2 - m2 was detected in 3/3 of gastritis cases by H. pylori with the cagA- genotype. These results are the first reported in our region and provide data of epidemiological interest.

[Gastrointestinal Kaposi's sarcoma associated to AIDS. Case report]. / Sarcoma de Kaposi gastrointestinal asociado a síndrome de inmunodeficiencia adquirida. Descripción de un caso.

In this paper, we describe a particular clinical case of gastrointestinal Kaposi's sarcoma associated with acquired immunodeficiency syndrome in a 51-year-old female patient who survived 6 years without anti-retroviral treatment after the diagnosis of HIV infection. The patient was admitted to our hospital with fever, skin lesions in both upper limbs and thighs (one day of evolution) and dry cough (about a month of evolution). She was admitted to the General Internal Medicine Service for control, diagnosis and treatment. An upper digestive bleeding was detected there. Once referred to our Gastroenterology Service, an appropriate selection of tests (anamnesis, gastric video endoscopy, histology) was carried out. In the upper gastric video endoscopy, several epithelial lesions were observed and a presumptive diagnosis of Kaposi's sarcoma was obtained. The diagnosis was finally confirmed by chain polymerase reaction (PCR) amplifcation of HHV8 DNA. This finding highlights the contribution of the molecular biology laboratory that allowed in this case the first molecular identification in our institution of the causative agent of Kaposi's syndrome with gastrointestinal manifestations.