A 40-year-old man comes to the office due to progressively worsening shortness of breath and nonproductive cough over the last 3 weeks. He also notes 2 months of fatigue, intermittent fever, and decreased appetite. He has lost 6 kg (13.2 lb) during this period. He has no other medical problems. He has a history of intravenous drug use and a 20-pack-year smoking history. The patient was released from a 2 year incarceration 6 months ago. Temperature is 38.3 C (100.9 F), blood pressure is 110/70 mm Hg, pulse is 90/min, and respirations are 18/min. The patient is in no distress but has mild temporal wasting. Crackles are present throughout the lung fields. Heart sounds are normal. There is mild hepatomegaly. Chest x-ray is shown below. What is the most likely diagnosis?

Question

A 40-year-old man comes to the office due to progressively worsening shortness of breath and nonproductive cough over the last 3 weeks.  He also notes 2 months of fatigue, intermittent fever, and decreased appetite.  He has lost 6 kg (13.2 lb) during this period.  He has no other medical problems.  He has a history of intravenous drug use and a 20-pack-year smoking history.  The patient was released from a 2 year incarceration 6 months ago.  Temperature is 38.3 C (100.9 F), blood pressure is 110/70 mm Hg, pulse is 90/min, and respirations are 18/min.  The patient is in no distress but has mild temporal wasting.  Crackles are present throughout the lung fields.  Heart sounds are normal.  There is mild hepatomegaly.  Chest x-ray is shown below.  What is the most likely diagnosis?

Quizplus · Accepted Answer

This patient presents with subacute symptoms (fatigue, fever, weight loss, cough) in the setting of intravenous drug use and recent incarceration. Chest radiograph shows a diffuse reticulonodular pattern (millet seed), raising suspicion for miliary tuberculosis (TB). Miliary TB is caused by the hematogenous spread of Mycobacterium tuberculosis. It may arise during primary infection or with reactivation. Subacute or chronic symptoms are common. Extrapulmonary disease may occur in the lymph nodes, liver, bones, and central nervous system. Chest radiograph Incarceration and substance abuse (tobacco and intravenous drug use) put this patient at high risk for TB exposure. Other common social risk factors for TB infection include group living and international travel to endemic areas. (Choice A) Hodgkin disease typically presents with painless lymphadenopathy and B symptoms (fatigue, weight loss, night sweats). Mediastinal mass is common. This patient has pulmonary symptoms and a diffuse reticulonodular pattern (not mediastinal mass) on chest x-ray, making TB much more likely. (Choice B) Metastatic disease to the lung typically presents with multiple masses, although patients occasionally present with a lymphangitic carcinomatosis (which may have a reticulonodular appearance). This patient has subacute fevers (uncommon in metastatic cancer) and multiple risk factors for TB. In addition, lung cancer would be somewhat uncommon at his age. (Choice C) Mycoplasma pneumonia can cause subacute fever, pulmonary symptoms, and a reticulonodular pattern on chest x-ray. It would be very rare for Mycoplasma to cause symptoms for 2 months; most cases are limited to 2-3 weeks. (Choice D) This patient is an intravenous drug user and is at risk for septic emboli. Septic emboli typically cause nodular and cavitary lesions (not reticulonodular patterns) on chest x-ray. In addition, 2 months of symptoms would be less likely than a more acute presentation. Educational objective: Miliary tuberculosis typically presents with subacute or chronic fevers, weight loss, fatigue, and pulmonary symptoms. Chest x-ray classically reveals a diffuse reticulonodular pattern (millet seed). The most common behavioral risk factor for tuberculosis in the United States is substance abuse.

A 40-Year-Old Man Comes to the Office Due to Progressively