Hallucinations and tremors due to oral therapeutic doses of erythromycin and methylprednisolone

Abstract

A 64-year-old electronic engineer, with a history of hypertension kept under control with irbesartan 300 mg/die and atenolol 100 mg/die, came to our observation 48 h after the onset of tremors and hallucinations. Six days before hospital admission the patient started amoxacillin-clavulanate 1 gr/tid for fever (37.5–38.5 C) and general discomfort, but this therapy was interrupted 3 days after for the onset of urticaria, and replaced with erythromycin (1 gr/bids) and methylprednisolone (16 mg/ bids), no antihistamines were used. Twenty-four hours after the beginning of this new therapy, the patient complained of visual and auditory hallucinations which he lived with particular anguish. Later, he also presented tremors that progressively compromised his common daily activities, i.e. eating, dressing, writing, walking and standing up. On admission, body temperature, heart rate and blood pressure were 36.7 C, 66/bpm rythmic and 105/70 mmHg, respectively. No signs of previous urticaria were present. Cardiovascular and respiratory examinations were normal. The liver was palpable at 2 cm below the right costal margin, without tenderness. There were neither clubbing nor superficial lymphadenopathies. Carotid pulses were symmetrically normal. The patient exhibited tremors of head and face, especially of mouth and tongue, and a postural tremor of upper and lower limbs, which increased during movement and altered stability during standing and walking. Alteration of balance and gait was due to the effect of tremor, not to cerebellar disorder or postural instability. Also writing was particularly difficult and uncertain (Fig. 1). Tremors were absent during sleep. The remaining neurological examination was normal, and in particular deep tendon reflexes, tactile, temperature and vibration sensation were normal. All laboratory exams (including thyroid and liver functions, and all electrolytes: sodium, potassium, chlorine, calcium, magnesium and phosphate) were normal. Blood, stool, and urine cultures were negative as well as an antibodies’ search for legionella, mycoplasma, chlamydia, toxoplasma and Epstein–Barr Virus. On the second day of hospitalization, an electroencephalogram showed a good organization of the activity, even if unstable due to drowsiness. Electrocardiogram, chest and cervical x-ray, abdominal ultrasound, echocolordoppler of carotid arteries and brain MRI scan were normal. In the hypothesis that the clinical situation could be due to the assumption of erythromycin and steroid therapy, we suspended these drugs immediately, and no other therapy was administrated. In the following days, the symptoms quickly improved with the disappearance of the hallucinations in about 48 h, and the progressive reduction of the tremors, with improvement in writing (Fig. 1), equilibrium M. Gallerani (&) B. Boari Division of Internal Medicine, Department of Medicine, St. Anna Hospital, Corso Giovecca, 203, 44100 Ferrara, Italy e-mail: m.gallerani@ospfe.it