Tick-borne illness is an uncommon but important cause of secondary headache, especially within the transplant population. Organ transplant recipients have a 2.3-fold relative risk of death and of severe, systemic infection. Identification of risk factors for tick-borne disease is essential to reduce morbidity and mortality in this patient population.

A middle-aged patient with history of a prior heart transplant was admitted with headache for four days. The pain was mild initially but soon worsened and was exacerbated by bright lights, coughing, and changes in head position. He had never experienced similar pain or migraine. Medications included daily sirolimus, tacrolimus, and prednisone. The patient lived in the rural Midwest.

The patient was afebrile and other vital signs were stable. Exam was notable for positive Jolt accentuation and negative Kernig/Brudzinski signs and no noticeable rashes. He was oriented but was unable to spell the word “world” backwards. Otherwise, exam was normal.

Lumbar puncture revealed clear CSF with 0 RBC/cumm, 0 Nucleated cells/cumm, Protein 57 mg/dL (H), Glucose 62 mg/dL (serum glucose 100 mg/dL). Bacterial/fungal cultures demonstrated no organisms on Cytospin gram staining. VZV, CMV, WNV, and HSV PCR analyses were sent. Other labs were significant for hyponatremia (132 mmol/L), leukopenia (1.9 K/cumm), microcytic anemia (Hgb 10.9 g/dL, MCV 74 fL), and thrombocytopenia (81 K/cumm). CT Head and MRI brain were normal. This patient’s CSF viral PCR studies returned negative. A qualitative blood PCR assay for Ehrlichia chaffeensis, E. ewingii, and E. canis returned positive. The patient received doxycycline for a 10-day course with improvement. 

Identification of tick-borne disease in patients with a history of chronic immune suppression is necessary to avoid complications related to this relatively uncommon cause of infection.