A 24-year-old woman from Lima, Peru, presented with a nine-month history of persistent right hemicraneal headache preceded by photopsia, associated to nausea and photophobia. Her medical history was relevant for migraine; she worked as a teacher at an orphanage and had travelled within the previous year to Morocco and Spain.
Seven months prior to presentation, she had been evaluated for this complaint; a head computed tomography (CT) angiography was performed which showed a hypodense, right occipital lesion with ill-defined borders and peripheral contrast enhancement (Figure 1); the study was followed by a brain magnetic resonance imaging (MRI), which confirmed the presence of a solid cortical formation of about 0.7 centimeters in the right occipital lobe, with an irregular border, associated with vasogenic edema. A biopsy of the lesion was performed, and it demonstrated a necrotizing granuloma, with no identification of acid-fast bacilli, a negative Mycobacterium tuberculosis tissue polymerase chain reaction (PCR), and no evidence of malignancy. The patient was then referred to the Infectious Diseases Department in order to rule out infectious causes of granulomatous brain lesions. Further workup demonstrated negative results for Histoplasma antibodies, Listeria monocytogenes (IgG), Leptospira (IgG-IgM), Hydatidosis (IgG), Borrelia burgdorferi (IgG-IgM), Coxsackie B Ab, E. histolytica Ab, Bartonella henselae (IgG-IgM), QuantiFERON TB, antinuclear antibodies, ANCA C-P, SS-A antibodies, SS-B antibodies, Rose Bengal, tube agglutination, 2-mercaptoethanol test, prozone phenomenon, and blocking antibodies.
After four months without a definitive diagnosis, she was readmitted after an episode of generalized tonic-clonic seizures. Serum and cerebrospinal fluid (CSF) tests were negative for histoplasmosis, paracoccidioidomycosis, vasculitis, and tuberculosis. Empiric treatment for cerebral tuberculosis (isoniazid 300 mg, rifampicin 600 mg, pyrazinamide 150 mg, and ethambutol 1200 mg/daily plus dexamethasone 6 mg/daily) therapy was started given the high prevalence of tuberculosis in Peru and the finding of a necrotizing granuloma in the brain biopsy, but the headache and photopsia persisted. Evaluation by Ophthalmology, which included fluorescein angiography, found bilateral optic papillitis without signs of uveitis. Further studies for granulomatosis demonstrated a switch in the Brucella panel tests, with positive plate agglutinations, positive Rose Bengal test, and positive (1/100) tube agglutination test; these tests were performed in three different laboratories, and all of them reported consistent results.
Specific brucellosis treatment was started with doxycycline 100 mg twice a day, trimethoprim-sulfamethoxazole 160/800 mg twice a day, and intravenous amikacin 1 g daily; she received amikacin only for the first 10 days and the other two antibiotics for twelve weeks. Corticosteroids doses were tapered gradually until total discontinuation at the end of the first month of specific therapy.
Clinical, laboratory, and radiological improvement was seen during the ambulatory 12-month follow-up visit; she did not have any other headache crisis, neither seizures nor visual disturbances.