A 72-year-old man arrives at the clinic complaining of deteriorating weakness, exhaustion, anorexia, and a 10-kg (22-lb) weight loss during the previous four months. He states that he feels satisfied with only a tiny bit of food since it doesn't taste as wonderful as it used to. The patient had blood streaks in his sputum two weeks ago and has had a morning cough for a number of years. His smoking history spans 50 packs. When examined, the patient shows signs of bitemporal wasting and a sunken face. His arms show obvious muscular atrophy and are quite slender. Right-sided wheeze is discovered during a lung examination. Chest x-ray reveals an irregular right perihilar mass. Which of the following is most likely contributing to this patient's muscle wasting?

Question

A 72-year-old man arrives at the clinic complaining of deteriorating weakness, exhaustion, anorexia, and a 10-kg (22-lb) weight loss during the previous four months. He states that he feels satisfied with only a tiny bit of food since it doesn't taste as wonderful as it used to. The patient had blood streaks in his sputum two weeks ago and has had a morning cough for a number of years. His smoking history spans 50 packs. When examined, the patient shows signs of bitemporal wasting and a sunken face. His arms show obvious muscular atrophy and are quite slender. Right-sided wheeze is discovered during a lung examination. Chest x-ray reveals an irregular right perihilar mass.  Which of the following is most likely contributing to this patient's muscle wasting?

Quizplus · Accepted Answer

Eductional Objective: An underlying systemic condition causes cachexia, a syndrome that includes anorexia, lethargy, anemia, weight loss, and widespread wasting. This patient's cachexia is probably a symptom of the lung tumor seen on his chest x-ray. Tumor necrosis factor (TNF) is a cytokine that results in cachexia in experimental animals as well as the necrosis of certain tumors in vitro. TNF--also known as cachectin-is one of the primary mediators of paraneoplastic cachexia, along with IL-1 and IL-6.
In response to infection and in some neoplastic cells, macrophages release TNF-. Its impact on the hypothalamus, which causes appetite suppression, explains its function in cachexia. Additionally, the basal metabolic rate rises.

A 72-Year-Old Man Arrives at the Clinic Complaining of Deteriorating