Sudden atelectasis and respiratory failure in a neutropenic patient: atypical presentation of pseudomembranous necrotizing bronchial aspergillosis.

Pseudomembranous necrotizing bronchial aspergillosis (PNBA) is a rare form of invasive aspergillosis with a very poor prognosis. The symptoms are non-specific, and the necrotizing plugs cause airway obstruction. Atelectasis and respiratory failure can be the initial manifestations.

Hepatitis B virus reactivation in a surface antigen-negative and antibody-positive patient after rituximab plus CHOP chemotherapy.

Rituximab is a monoclonal antibody that targets B-lymphocytes, and it is widely used to treat non-Hodgkin's lymphoma. However, its use has been implicated in HBV reactivation that's related with the immunosuppressive effects of rituximab. Although the majority of reactivations occur in hepatitis B carriers, a few cases of reactivation have been reported in HBsAg negative patients.