Background: Pulmonary alveolar proteinosis (PAP) poses a risk of opportunistic infections with a variety of organisms with Nocardia being the most common pathogen followed by mycobacteria and fungi. Case presentation: A 7-year-old female child, presented with headache and multiple episodes of vomiting. There was no fever or altered sensorium. On examination, there were no focal deficits or cranial nerve palsies. An MRI brain showed a small T2 hyperintense lesion in the left superior parietal lobe suggestive of an abscess. She was diagnosed as PAP based on CT chest and bronchioloalveolar lavage 7 months earlier and treated with corticosteroids. A left parietooccipital craniotomy was done with drainage of abscess and abscess wall excision. Histopathology revealed a suppurative lesion with slender septate acute angle branching hyphae which were positive on fungal stains. Culture done on the pus was positive for Aspergillus fumigatus. The patient was treated with voriconazole and stable at 1 year follow-up. Conclusion: Opportunistic infections are common in patients diagnosed with PAP. High index of clinical suspicion and early diagnosis are important for favorable outcome.

Dural-based B cell lymphomas are rare and have a female preponderance. A 60-year-old Asian man with a history of trivial trauma presented with generalised tonic clonic seizures and headache. Imaging and clinical work-up was done. A temporoparietal subdural lesion with no evidence of systemic lymphoma was detected. Intraoperatively, a dural-based mass lesion was seen with thickened dura and biopsy-proven B cell lymphoma, and the patient was then kept on chemotherapy. A suspicion of this rare entity should be considered in imaging of dural-based lesions.

T cell/histiocyte-rich large B cell lymphoma (THRLBCL) is an unusual variant of diffuse large B cell lymphoma with poor prognosis. We describe a case of THRLBCL with an uncommon isolated spinal involvement. A 37-year-old male came to the neurosurgery outpatient department with weakness of both upper and lower limbs. Histopathology and immunohistochemistry revealed features consistent with THRLBCL. The patient was treated with D5-D6 laminectomy followed by six cycles of chemotherapy (CHOP; cyclophosphamide, hydroxydaunorubicin, oncovin, prednisolone) and was disease free for 5 years until he had relapse of disease at the same location in 2016 for which he is receiving palliative radiation therapy. Isolated spinal involvement as the first or only manifestation of THRLBCL is very rare and has been described very occasionally in the literature. It is important to correctly diagnose this entity and differentiate it from its mimics because of different prognostic and therapeutic implications.