An unusual presentation of an invasive infection

A 59-year-old-man of Indian-origin with poorly controlled diabetes was admitted after having collapsed at home with severe left sided ear ache, headache, vertigo, vomiting and confusion. Over the previous year, he had recurrent episodes of left sided ear ache. Blood tests on admission revealed: CRP 45, WBC 11.4 with an absolute eosinophil count of 0.8 (peaked to 1.8 during the course). MRI head revealed fluid in left middle ear and mastoid with base of skull osteomyelitis/abscess1. Patient was treated with a prolonged course of broad-spectrum antibiotics and a mastoidectomy was performed. Microscopy and culture of tissue samples were negative for bacterial, fungal, and mycobacterial growth with no signs of acute inflammation on histology. He initially seemed to respond to therapy and was discharged home on a prolonged course of oral antibiotics. He was readmitted 2 months later with recurrence of original symptoms and also tinnitus, dysphagia, anorexia, low-grade pyrexia and a soft tissue swelling behind the neck.
CT-guided biopsy of the occipital lesion showed only chronic inflammation. CSF examination showed 4 lymphocytes, elevated protein (1.57gm/L), and normal glucose. He was commenced on empiric anti-TB therapy at this stage. CSF and tissue samples were negative for routine cultures, cryptococcal antigen, TB PCR, Pan fungal PCR2. He was HIV seronegative and quantiferon-TB test was negative. Patient continued to deteriorate both clinically and radiologically despite being on 6-weeks of empirical anti-TB treatment, and a 2-day-course of Ivormectin for a positive strongyloides serology. A diagnostic procedure was performed.