A 64-year-old woman felt sudden onset severe continuous headache, especially in the front temporal occipitoparietal areas, accompanied by intermittent nausea and vomiting on 21st June, 2020. Meanwhile, she felt tinnitus and had a feeling of swelling in the right ear, whereas, without fever, lateral limb weakness, blurred vision and loss of consciousness. Electroencephalogram (EEG) examination showed mild abnormality. Upon being admitted on 26th June, the patient developed a fever with the highest point reaching 39.5℃. A neurological examination revealed obvious nuchal rigidity with four transverse fingers under the chin. However, he had intact sensation and full limb power with a negative bilateral Babinski sign.
Cranial magnetic resonance imaging (MRI) revealed abnormal hyperintensities signals in the left head of caudate nucleus, with T1-weighted sequence of hypointensity, T2 -weighted sequence of hyperintensity, FLAIR sequence of slightly hyperintensity, and diffusion restriction on diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) at the corresponding position. No significant abnormality was observed in the cerebral magnetic resonance angiography (MRA). Therefore, we further conducted cranial SPGR and meningeal CUBE enhancement, which displayed the ring-enhancement with consistent thickness next to the anterior horn of the left lateral ventricle and the meningeal linear enhancement in the left occipital lobe, suggesting a high probability of infectious diseases of brain abscess and meningitis (Fig. 1A-1J).
Blood analysis showed elevated levels of neutrophile granulocyte percentage (84.6%), C-reactive protein (CRP) (238.88mg/L), erythrocyte sedimentation rate (ESR) (82mm/h), and procalcitonin (HCT) (0.228ng/ml). Accordingly, we gave the patient anti-infective therapy of ceftriaxone (2g Q12h) and metronidazole (0.5g Q8h) by experience. The temperature began to go down, fluctuating between 37.0℃ and 37.8℃. The antinuclear antibody, hepatitis and tumor screening, coagulation test, thyroid function, vasculitis screening, brucella agglutination test, tiger red plate agglutination test, Brucella IgG antibody detection, Widal and Weil-Felix reaction, anti-human globulin test, T cell test for tuberculous infection, HIV, TP, blood culture, cardiac ultrasound, chest CT, cranial CT and abdomen CT showed no obvious abnormality. The CT scan of temporal bone and paranasal sinuses, which showed right otitis mastoidea (Fig. 1K, 1L). The otolaryngology consultation considered the right otitis media, and 0.2ml of sallow exudate was extracted.
The cerebral spinal fluid (CSF) common results on 29th June were shown in Table 1 and Fig. 2. The CSF cultures, acid-fast dyeing, and India ink staining were negative. The next generation sequencing (NGS) of CSF showed the infection of K pneumoniae. Ceftriaxone and metronidazole were replaced by meropenem to broaden the antimicrobial spectrum, and 20%mannitol (125ml Q8h) was added to reduce the intracranial pressure. The patient's body temperature dropped below 37.3℃ and the symptom of headache and fever alleviated obviously. The CSF results got better on 6th July (Table 1, Fig. 2). The patient asked for discharge. The cranial SPGR and meningeal CUBE enhancement on 10th July displayed the abscess cavity and wall was larger and thicker than before (Fig. 3A-3D). The patient went back to the local hospital and gave the ceftriaxone injection for 8 weeks. The CSF results got better on 22th July (Table 1, Fig. 2). Almost two months after the onset (31st August), the CSF results returned nearly to normal (Table 1, Fig. 2), and the lesions in MRI nearly disappeared (Fig. 3E-3J). She didn't complain of anything uncomfortable until 28th December.