About H. pylori true are all except
|A||Cag A protein is present in infected patients with ulcers or gastric adenocarcinoma|
|B||Associated with MALT|
|C||Triple regimens is the best treatment available|
|D||All are correct|
a. Among this multitude of proteins there are factors that are essential determinants of H. pylori–mediated pathogenesis and colonization, such as the outer membrane protein (Hop proteins), urease, and the vacuolating cytotoxin (Vac A).
b. Moreover, the majority of H. pylori strains contain a genomic fragment that encodes the cag pathogenicity island (cag-PAI).
c. Several of the genes that make up cag-PAI encode components of a type IV secretion island that translocates Cag A into host cells. Once in the cell, Cag A activates a series of cellular events important in cell growth and cytokine production.
d. The first step in infection by H. pylori is dependent on the bacteria's motility and its ability to produce urease.
e. Urease produces ammonia from urea, an essential step in alkalinizing the surrounding pH.
f. H. pylori infection is virtually always associated with a chronic active gastritis, but only 10–15% of infected individuals develop frank peptic ulceration.
g. Initial studies suggested that >90% of all DUs were associated with H. pylori, but H. pylori is present in only 30–60% of individuals with GUs and 50–70% of patients with DUs.
h. The pathophysiology of ulcers not associated with H. pylori or NSAID ingestion [or the rare Zollinger-Ellison syndrome (ZES)] is becoming more relevant as the incidence of H. pylori is dropping, particularly in the Western world (see below).
i. Multiple drugs have been evaluated in the therapy of H. pylori. No single agent is effective in eradicating the organism.
j. Combination therapy for 14 days provides the greatest efficacy. A shorter course administration (7–10 days), although attractive, has not proved as successful as the 14-day regimens.
k. The agents used with the greatest frequency include amoxicillin, metronidazole, tetracycline, clarithromycin, and bismuth compounds.