Cerebellar Symptoms: An Uncommon Presentation of Legionnaires' Disease

A 27- year-old previously healthy man presented to the emergency department with a 3-day history of confusion, urinary retention, cough, slurred speech, intermittent vertigo, and unsteady gait after being started on outpatient abx for diagnosis of community acquired pneumonia at an outside facility. On presentation, his vital signs were significant for a Temp. of 102.4 F, a HR of 118 bpm, a RR of 22 bpm, a BP of 135/75 mmHg, O2 sats down to the 80s% with a new oxygen requirement of 3 L/min. His neurological exam was remarkable for dysarthria, a wide based and unsteady gait, forward drift on standing, bilateral dysmetria and was otherwise non-focal. Bilateral basilar rales were noted on lung exam. Initial workup was significant for a sodium level of 129, potassium 3.1, AST 178, ALT 31. His urine legionella antigen test was positive and COVID-19 PCR test was negative. CT of the chest demonstrated multifocal pneumonia. The predominant neurological picture on presentation warranted a lumbar puncture as well as an MRI of the brain, both of which came back negative. HIV test was negative as well. The spectrum of neurological manifestations of legionnaire's disease is quite wide ranging from simple headaches to acute disseminated encephalomyelitis (ADEM). While up to 40% of patients may present with headaches and some confusion, the specific cerebellar presentation is quite rare and has been described in case reports. According to Shelburne(1), there has been instances where the neurological manifestations have lasted up to 3 years after resolution of the pulmonary disease. In a review article detailing 29 cases of cerebellar dysfunction in Legionnaire's disease, a lumbar puncture performed in 16 of the cases showed that the majority had no abnormalities in CSF studies. The propensity for Legionella to specifically manifest as cerebellar Sx remains to be studied. Interestingly, another case report of two patients with neurological symptoms, showed hypoperfusion of the cerebellar and frontal lobes on single photon emission while CT and MRI imaging of the brain were normal. We add to the literature another 'cerebellar' presentation of Legionnaire's disease.