Fibrotic lung disease

Answer Explanation:

• Amiodarone is the correct answer because it is a well-known cause of drug-induced lung fibrosis. This is a serious side effect that can occur in patients who are taking this medication for heart rhythm disorders.
• Gentamicin, Metformin, Allopurinol, and Propranolol are not typically associated with lung fibrosis. Although these drugs can have other side effects, they are not known to cause fibrotic changes in the lung tissue.

Overview of Drug-Induced Lung Fibrosis:

• Drug-induced lung fibrosis is a form of interstitial lung disease that can occur as a side effect of certain medications.
• It involves the scarring or thickening of the lung tissue, which can lead to difficulty breathing and other respiratory symptoms.
• Amiodarone, a medication used to treat heart rhythm disorders, is one of the most common drugs associated with this condition. The risk of developing lung fibrosis increases with higher doses and longer duration of treatment with this drug.
• Other drugs that can cause lung fibrosis include certain chemotherapy drugs, some antibiotics, and some anti-inflammatory drugs.
• Diagnosis is usually based on the patient’s medical history, physical examination, and imaging studies such as chest X-ray or CT scan. Lung function tests and sometimes a lung biopsy may also be needed.
• Treatment involves discontinuing the offending drug (if possible) and managing symptoms. In severe cases, oxygen therapy or lung transplantation may be required.

Answer Explanation:

• The correct answer is ‘An elevated serum angiotensin-converting enzyme’. Sarcoidosis is often associated with increased levels of serum angiotensin-converting enzyme (ACE) due to the high activity of this enzyme in the epithelioid cells forming the granulomas.

Incorrect Options Explanation:

• ‘Presentation in the first decade of life’ is incorrect. Sarcoidosis typically presents in adults aged 20-40 years old.
• ‘Caseating granulomas on histological examination’ is incorrect. Sarcoidosis is characterized by non-caseating granulomas, not caseating granulomas.
• ‘Erythema multiforme’ is incorrect. While skin manifestations can occur in sarcoidosis, erythema multiforme is not a typical feature.
• ‘Hypocalcaemia’ is incorrect. Hypercalcaemia, not hypocalcaemia, is a potential feature of sarcoidosis due to increased production of vitamin D by macrophages in the granulomas.

Overview of Sarcoidosis:

• Sarcoidosis is a systemic granulomatous disease of unknown etiology.
• It most commonly affects adults aged 20-40 years old.
• It is characterized by the formation of non-caseating granulomas in various organs, most commonly the lungs and lymph nodes.
• Common symptoms include cough, dyspnea, and chest pain. However, the disease can also be asymptomatic and discovered incidentally on imaging.
• Other potential manifestations include skin lesions (such as erythema nodosum), eye inflammation, and hypercalcaemia.
• Diagnosis is typically confirmed by histological examination showing non-caseating granulomas.
• Increased serum ACE levels can be seen but are not diagnostic.
• Treatment depends on the severity and organ involvement, but may include corticosteroids or other immunosuppressive agents.