A 35-year-old man was hospitalized with fever, chest pain, and cough of 2 weeks' duration. These symptoms persisted despite 4 days of antibiotic treatment with IV ceftriaxone sodium 2 g/d. The patient was a nonsmoker with an unremarkable medical history who worked as a herdsman and lived in the Shigate region of Tibet, China.

A 21-year-old Hispanic woman with no significant medical history presented with complaints of progressive skin lesions for 3 months, associated with dyspnea and scant hemoptysis for 1 week. She initially developed painless subcutaneous nodules on her right forearm, which progressed to superficial ulcers and gradually spread to involve bilateral arms, thighs, chest, abdomen, and gluteal region. The lesions spared the head, neck, palms, and soles. She also reported fatigue and a 20-pound weight loss. An initial outpatient punch biopsy from a leg ulcer revealed nonspecific granulomatous inflammation treated with prednisone and hydroxychloroquine without improvement. A review of systems was negative for fever, chills, night sweats, arthralgias, lymphadenopathy, mucosal ulceration, or bleeding. She was born in El Salvador but had spent most of her life in New York. She did not report any recent international travel or sick contacts. There was no personal or family history of immunodeficiency or malignancies.

A 60-year-old man was referred to a pulmonologist evaluation with persistent dyspnea and cough 1 month after discharge for an acute respiratory failure caused by Legionella pneumophila pneumonia, which required invasive mechanical ventilation. Chest CT scan performed during hospitalization showed lobar consolidation of upper left lobe (Fig 1A). Bronchial culture revealed L pneumophila; the patient was treated with levofloxacin and supported with invasive mechanical ventilation for 2 weeks. Chest radiograph after extubation showed almost complete resolution of infiltrates. After 1 month, the patient still complained of dyspnea and a new chest CT scan was performed: the consolidation migrated (Fig 1B; Video 1).

A 49-year-old woman with a history of right breast cancer status post radiation therapy presented to our ED with increasing chest pain, exertional dyspnea, fatigue, and dizziness for several weeks. She denied syncope or near-syncope, and she had no personal or family history of cardiac disease. Her outpatient medications included tamoxifen and venlafaxine.

A 54-year-old Indian woman presented with low-grade fever and cough with expectoration for 1 month. Fever was not associated with any chills or night sweats. Expectoration was minimal in amount and mucoid in nature. Her appetite was decreased, without any significant weight loss. She denied any history of dyspnea or hemoptysis. The patient was diagnosed with rheumatoid arthritis 1 year previously and was initially started on methotrexate and short-term glucocorticoids. At the time of presentation, she was taking methotrexate 15 mg weekly and hydroxychloroquine 200 mg daily. Her joint disease was controlled on immunomodulators. She had no other comorbid condition, and she was a never smoker. She neither traveled within or outside India in the past nor came in contact with patients with pulmonary TB. A chest radiograph was done because a prior workup showed an ill-defined solitary nodular lesion in the right lower zone. She took a course of amoxicillin-clavulanate, but that was of no benefit.

In this second article on medieval Arabic medical discussions on sleep, I show that Ibn Sīnā's pneumatic paradigm of sleep opened up new research pathways for subsequent physicians in Islamic societies. Opposing those who posit a decline in scientific activity post-1200 in these societies, I show that Ibn al-Nafīs (d. 1288), Ibn al-Quff (d. 1286), and Quṭb al-Dīn al-Shīrāzī (d. 1311), among others, raised and answered new questions to highlight the (possible) active role played by the brain in sleep onset and the strengthening of certain brain activities during sleep. They also continued to investigate the (three) stages of sleep and paid attention to different breathing patterns, in addition to pulse, during each stage. Finally, they also applied the pneumatic paradigm in new ways to understand the broader impact of certain medical conditions on sleep.