A 50-year-old man, newly diagnosed with HIV infection with a CD4 count of 5 cells, complained of prolonged fever, productive cough and dyspnea. 

Investigation results were as shown above.

Questions:  

1. Describe the chest X-ray findings

2. Describe the sputum Gram and MAFS stain and identify the organism(s)

3. What is the provisional diagnosis?

ANSWERs

1. Chest X-ray findings : Well-defined border cavitary lesion at Rt middle lung zone, without ground-glass opacity around the lesions. 

    Differential diagnosis from the CXR includes

    - Infectious causes : TB, fungal infections (cryptococcosis, histoplasmosis)

    - Non-infectious causes : squamous cell CA 

2. Sputum gram stain : Pleomorphic small gram positive coccobacilli

   MAFS stain : Positive 

3. Provisional diagnosis : Pulmonary rhodococcosis 

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