BIOS 256 Week 2 Case Study Lower GI

Student Name

Chamberlain University

BIOS-256: Anatomy & Physiology IV with Lab

Prof. Name

Date

History

Mr. D, a 60-year-old male, presented with a 24-hour history of fever, abdominal discomfort, nausea, and reduced appetite. He reported no recent changes in dietary habits, denied eating outside food, and had not traveled recently. His medical history revealed a screening colonoscopy five years ago, which identified diverticula in the colon, although he had been asymptomatic since then.

Physical Examination

On clinical assessment, Mr. D appeared fatigued and in visible distress due to abdominal pain. Palpation of the abdomen revealed tenderness, indicating localized inflammation.

Laboratory Results/Tests

Diagnostic tests were performed to assess Mr. D’s condition. The findings are summarized in the table below:

Assessment and Plan

Based on clinical presentation and diagnostic imaging, Mr. D was diagnosed with diverticulitis, an inflammatory condition involving diverticula (small pouches in the colon wall). Contributing risk factors include a low-fiber diet, sedentary lifestyle, and chronic constipation (Strate & Morris, 2019). The management plan typically involves bowel rest (liquid diet), hydration, and antibiotic therapy. In severe cases, surgical intervention may be necessary.

Deliverables

1. Path of Chyme and Feces from the Duodenum to the Anus

After entering the duodenum from the stomach, chyme mixes with bile and pancreatic enzymes, initiating nutrient breakdown. Through segmentation and peristalsis, chyme progresses into the jejunum, where villi and microvilli absorb most macronutrients and water. By the time chyme reaches the ileum, the majority of digestion and absorption is complete, with the ileum also facilitating vitamin B12 and bile salt absorption.

Undigested residues then pass into the caecum, the first section of the large intestine. The colon reabsorbs water and electrolytes while gut microbiota ferment residual carbohydrates, producing short-chain fatty acids and vitamins (e.g., vitamin K). In the sigmoid colon, stool becomes more solid and is temporarily stored before being pushed into the rectum. Finally, stretch receptors in the rectum trigger defecation, with the stool exiting through the anus, regulated by sphincter muscles.

2. Two Important Functions of the Small Intestine

3. Two Important Functions of the Large Intestine

4. Predict the Location of Pain in Diverticulitis

Diverticulitis commonly affects the sigmoid colon, situated in the left lower quadrant (LLQ) of the abdomen. Consequently, patients usually report localized LLQ pain, which may intensify with movement or palpation.

5. Functions of the Peritoneum

The peritoneum is a double-layered serous membrane that lines the abdominal cavity. Its key functions are:

• Providing structural support and protection for abdominal organs.

• Acting as a conduit for blood vessels, nerves, and lymphatic vessels.

• Reducing friction between organs through secretion of serous fluid.

• Helping to localize infections by forming adhesions.

BIOS-256 Week 2 Case Study: Lower GI Summary

Mr. D’s case highlights the importance of recognizing clinical features of diverticulitis and correlating them with diagnostic findings. Understanding the gastrointestinal (GI) tract’s structure and functions supports accurate assessment, appropriate interventions, and effective patient education regarding lifestyle modifications such as a high-fiber diet and adequate hydration to prevent recurrence.

References

Strate, L. L., & Morris, A. M. (2019). Epidemiology, pathophysiology, and treatment of diverticulitis. Gastroenterology, 156(5), 1282–1298. https://doi.org/10.1053/j.gastro.2018.12.033

Tortora, G. J., & Derrickson, B. H. (2017). Principles of anatomy and physiology (15th ed.). Wiley.