Murine typhus presenting as subacute meningoencephalitis

Abstract

Murine typhus is a febrile systemic illness, presenting with headache and undulating fever. Neurological involvement is considered a rare complication. During 1994 and 1995, 34 patients admitted to our hospital were diagnosed as having murine typhus. Five of these patients presented with a syndrome of subacute "aseptic" meningitis or meningoencephalitis. Three had bilateral papilloedema and 2 had focal neurological signs. None had a rash or other systemic findings suggestive of rickettsial disease. The diagnosis was based on serum and cerebrospinal fluid serology and on prompt response to doxycycline therapy. These cases suggest that neurological involvement in murine typhus is more common than previously suspected and that murine typhus should be included in the differential diagnosis of subacute meningitis in endemic areas.

Abducens Nerve Palsy and Meningitis by Rickettsia typhi

“…Pleocytosis of the CSF is usually present with a white cell count of 10-640 cells/mm 3 and a predominance of mononuclear cells, a normal glucose level, and normal-to-elevated total protein levels. 16 These CSF profiles are similar to those of leptospirosis, viral and tuberculous meningitis. 38 This may result in the use of inappropriate antimicrobial and antiviral therapies and in some cases long-term therapy for presumed tuberculous meningitis.…”

“…In a case series of five patients with R. typhi meningoencephalitis published in 1998, elevated intracranial pressure was found in only one of the three patients with papilledema. 16 Sixth nerve palsy and bilateral papilledema were present in one patient, but her CSF opening pressure was within normal limit (5 cmH 2 O). In the year 1977, Manor and colleagues 18 reported a case of severe bilateral papilledema in the absence of intracranial hypertension in murine typhus.…”

“…The presence of papilledema and/or sixth nerve palsy in these cases cannot be explained by raised intracranial pressure and brain imaging, suggesting that the cranial nerves may be directly involved by a separate process, which could be vasculitic in nature. 16,[29][30][31] Signal alteration in the splenium of corpus callosum on brain MR imaging has been reported in a variety of conditions including infections, demyelination, ischemia, and metabolic abnormalities. 32 Infectious etiology associated with splenium injury include viruses (e.g., HIV, HHV6, rotavirus, measles), bacterial (e.g., Salmonella, Escherichia coli O157:H7, tuberculosis, Lyme disease) and parasites (e.g., malaria, toxoplasmosis, cysticercosis).…”

“…Unlike other forms of rickettsial infections, these changes rarely progress to thrombotic occlusion, microinfarctions, and microhemorrhages, thus explaining the rapid reversibility of most neurological signs. 16 Not all patients with rickettsial meningitis have meningeal signs. 37 In rickettsial meningitis, the cerebrospinal fluid findings are consistent with aseptic meningitis.…”

“…[13][14][15] Patients with murine typhus involving the central nervous system typically present with headache, fever, and neck stiffness 10 days to 3 weeks after the initial onset of febrile illness. 16,17 More serious neurological signs, such as diplopia, papilledema, and facial paralysis have also been reported. [17][18][19] Here, we report two patients with murine typhus who developed aseptic meningitis with sixth nerve palsy.…”