A 47year old Caucasian man came to the emergency room with of fever, severe headaches, severe body aches and pain for 4days. Headaches worsened and he developed photophobia on day 5. He was taking Bactrim for an infected left arm wound which he stopped after these symptoms started.
On examination, he was acutely ill looking, febrile, temp 102, tachycardic, no neck stiffness, he was alert and oriented, with no focal neurological deficit. Other systems were normal.
He had normal complete blood count. Liver enzymes were mildly elevated (Alk phos 116U/L, AST 111,U/L ALT 113U/L) Total bilirubin was 3.5mg/dl, INR was 1.0, lactate was 2.0. Influenza screen and mononucleosis screen test were negative. lumbar puncture with CSF analysis showed of elevated WBC 19, with 58% lymphocytes, 35% monocytes, 3% neutrophils, and 1% eosinophils. CSF protein was elevated at 63mg/dl, glucose was normal.
He was commenced on ceftriaxone and vancomycin. CSF Culture came back negative and antibiotics were stopped. CSF HSV and Enterococcus PCR were negative. Hemoglobin decreased from 13.5g/dl to 9g/dl over 3days with no evidence of gross blood loss. He had elevated LDH ( 517U/L) low Haptoglobulin and high reticulocytes count (3%). Antiglobulin test was negative. His G-6-PD level was normal
Patient was diagnosed with aseptic meningitis and hemolytic anemia. Differential included Bactrim related aseptic meningitis but due to his ‘influenza like’ symptoms in an endemic area for Ehrlichiosis, Ehrlichiosis was considered and he was commenced on doxycycline.
PCR for Ehrlichia chaffeensis DNA was positive in both blood and CSF. His symptoms improved initially then worsened so he did not complete the course of doxycycline.
Discussion: Ehrlichiosis is a tick borne illness first described in 1986. It is caused by 4 types of Ehrlichia species. The vector for Ehrlichia Chaffeensis is the lone star tick, Amblyomma and the reservoir is the white tail deer. It is endemic in southeast, south, central and Midwestern states. The tick needs to be attached for 4 to 48hrs before it can transmit the disease. Incubation period is 9days. Often described as ‘influenza like’ Symptoms, they include fever, headache, myalgia and arthralgia. 42% of infected patients require hospitalization. 17% develop life threatening complication such as heart failure, hepatic insufficiency or failure, aseptic meningitis, interstitial pneumonia, Acute Respiratory Disease Syndrome, hemorrhage and Septic shock syndrome. It has a fatality rate of 3%. Old age, immunocompromised status and prior use of sulphonamide antibiotics has been associated with severe form of the disease. CNS involvement presents as meningitis or meningoencephalitis and in some cases, coma, seizures and cranial nerve palsy. Since symptoms are initially non specific you need to have high index of suspicion to make diagnosis.
Treatment of choice is doxycycline followed by rifampicin and chloramphenicol. This patient had sulphonamide which is associated with the severe form of the disease. He also had worsening of his symptoms after initial improvement with therapy. This is a Jarisch-Herxheimer reaction and has been known to occur with therapy.
Conclusions: Ehrlichiosis is a rare cause of aseptic meningitis. High index of suspicion is required for prompt diagnosis and treatment. Patient should also be counseled on possible Jarisch-Herxheimer reaction during treatment to ensure compliance with the antibiotics.
To cite this abstract:Ugbarugba E. Aseptic Meningitis Secondary to Ehrlichia Chaffeensis. Abstract published at Hospital Medicine 2015, March 29-April 1, National Harbor, Md. Abstract 717. Journal of Hospital Medicine. 2015; 10 (suppl 2). https://www.shmabstracts.com/abstract/aseptic-meningitis-secondary-to-ehrlichia-chaffeensis/. Accessed October 23, 2019.