CASE HISTORY
Renita,a 67-year-old woman,complained to her physician of having persistent diarrhea with weight loss,bloating,and excess flatulence (passing gas).Renita also said her stools looked greasy,which the physician knew as a sign that ingested fat was not being absorbed.A blood test revealed that the woman's vitamin B₁₂ level was abnormally low.Cultures of fecal specimens failed to find any typical bacterial pathogens that could cause diarrhea.However,the decreased vitamin B₁₂ level and excess fat in the stool suggested that the woman had a malabsorption disease.The physician,initially perplexed,suddenly realized that the cause could be small intestine bacterial overgrowth disease,a diagnosis confirmed by aspirating fluid from the jejunum (small intestine).The laboratory discovered abnormally high numbers of facultative and anaerobic bacteria in the fluid,including Streptococcus,Escherichia coli,Lactobacillus,and Bacteroides.Fermentation by these organisms produced the bloating and flatulence.Antibiotic treatment corrected the syndrome.
Which best describes the relationship between Renita and her microbiome in this case study?

Question

Quizplus · Accepted Answer

The symptoms and laboratory findings suggest that Renita had small intestine bacterial overgrowth disease, which occurs when microbiota from one portion of the GI tract thrive in another area where they are not normally found. The decreased vitamin B12 level and excess fat in the stool are signs of malabsorption, which could occur due to a reduction of bile production or disruption of the normal anatomy and function of the digestive tract. The abnormal growth of bacteria in the jejunum would have produced excess flatulence and bloating due to fermentation in the gut. Antibiotic treatment corrected the syndrome by reducing the population of overgrown bacteria. There is no evidence of pathogens being present in Renita's jejunum, previous antibiotic use, or a failure of her immune system to reduce bacterial growth.

CASE HISTORY Renita,a 67-Year-Old Woman,complained to Her Physician of Having Persistent Diarrhea