Hole in a Diaphragm

From Mike:
I thought this insight might be helpful as there are many medical school teachers and medical students and doctors on my email list.

This is an interesting case of a hole in the diaphragm (right side) with lung tissue obstruction right above it.

Video x-rays I have watched show the hole as being a weakened, shrunken portion of the diaphragm. Whenever the diaphragm weakens it loses its ability to squeeze the sponge of the lungs right above it. Then debris collects. The lungs are a lot like a kitchen sponge that you need to squeeze to allow water to enter then squeeze again to force the debris out of the sponge. The lungs are very similar in this way.

See Diaphragm Development.

A 44-year-old man with acute myelogenous leukemia presented with mild pleuritic chest discomfort of several days' duration and one episode of blood-tinged sputum. In general he felt well and denied shortness of breath. Vital signs were normal, and he did not have a fever. Physical examination, including chest examination, was normal.

The patient had been diagnosed with leukemia two months previously, and induction therapy had been given successfully. Two weeks prior to this current presentation, high-dose cytarabine (3g/m² every 12 hours for 3 days) was given as consolidation chemotherapy. His medications at this time were ipratropium inhaler, acetaminophen, prochlorperazine, venlafaxine, fluvastatin, naproxen, and allopurinol.

His WBC count was 500 x 10⁶/L, with an absolute neutrophil count of 100 x 10⁶/L. Chest radiograph showed interstitial infiltrates bilaterally. Sputum was insufficient for examination. Bronchoalveolar lavage revealed no organisms on Gram's or acid-fast stain. Direct fluorescent antibody testing for Pneumocystis carinii and Legionella pneumophila was negative. Cultures were obtained.

What is your diagnosis?

What is your suggested approach?