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Murine typhus presenting as pseudotumor cerebri

Published:January 30, 2021DOI:https://doi.org/10.1016/j.jcjo.2021.01.013
      Murine typhus is an acute infection transmitted by rodent or cat fleas carrying gram-negative, obligate intracellular bacteria, Rickettsia typhi. This vector for transmission is most often carried on rodents, but opossums are thought to be a reservoir in suburban settings.
      • Murray K.O.
      • Evert N.
      • Mayes B.
      • et al.
      Typhus group Rickettsiosis, Texas, USA, 2003–2013.
      Associated with overcrowding, pollution, and poor hygiene, murine typhus has been documented worldwide, but the majority of cases in the United States are in Texas and California.
      • Civen R.
      • Ngo V.
      Murine typhus: an unrecognized suburban vectorborne disease.
      Symptoms of murine typhus can be nonspecific, and they typically appear 7–14 days after infection. Patients most often present with recurrent fever, maculopapular rash, and headache, but arthralgia, cough, and abdominal pain can also be present.
      • Civen R.
      • Ngo V.
      Murine typhus: an unrecognized suburban vectorborne disease.
      ,
      • Masalha R.
      • Merkin-Zaborsky H.
      • Matar M.
      • Zirkin H.J.
      • Wirguin I.
      • Herishanu Y.O.
      Murine typhus presenting as subacute meningoencephalitis.
      Neurological symptoms are extremely rare, occurring in only 2%–5% of cases, and historically include altered mental status, seizures, or aseptic meningitis.
      • Masalha R.
      • Merkin-Zaborsky H.
      • Matar M.
      • Zirkin H.J.
      • Wirguin I.
      • Herishanu Y.O.
      Murine typhus presenting as subacute meningoencephalitis.
      We present a rare case of intracranial hypertension, papilledema, and visual disturbance secondary to Rickettsia typhi infection. To our knowledge, only three cases of this nature have been reported to date.

      Case Report

      A 31-year-old African American woman presented with acute, painless, binocular loss of vision. She also had a ten day history of acute intractable vomiting with nausea, chills, recurrent fevers up to 103°F, neck stiffness, myalgias, diarrhea, and left-upper-quadrant abdominal pain. She reported headaches behind the left eye with radiation to the left occipital region, which was noticeably different from her usual migraine pattern. On examination, neck pain was elicited in the occipital area, but there was no neck stiffness or Brudzinski sign. Past medical history was significant for hypertension, diabetes mellitus type II, migraines, and obesity (body mass index 34.3). She had no recent travel, animal exposure, or sick contacts.
      Cranial magnetic resonance imaging (MRI) of the head and magnetic resonance venography with contrast were normal (Fig. 1, Fig. 2). MRI of the spine was normal. Laboratory testing revealed an elevated C-reactive protein of 19.96 (normal <8 mg/dL), an erythrocyte sedimentation rate of 27 mm/h (normal 0–20 mm/hr), and elevated liver enzymes (alkaline phosphatase of 410 U/L (normal 35–104 U/L), aspartate transaminase of 117 U/L (normal 10–35 U/L), and alanine transaminase of 126 U/L (normal 5–50 U/L). Blood and sputum cultures showed no growth. Lumbar puncture revealed an elevated opening pressure of 34 cmH2O (normal 7–18 cmH2O), but cerebrospinal fluid composition was normal. Ophthalmic examination showed visual acuity of 20/20 in the OD and OS. She had reactive pupils with no anisocoria or relative afferent pupillary defect. The anterior segment was within normal limits, and intraocular pressures were 15 OD and 16 OS. Automated perimetry 24-2 Humphrey visual field testing showed a superior arcuate defect and inferior nasal step OD and snonspecific scatter OS. Dilated fundus exam showed Frisen grade 1 disc edema bilaterally (OU) (Fig. 3), which was confirmed with optical coherence tomography (Fig. 4).
      Fig 1
      Fig. 1Sagittal T1 Fluid Attenuated Inversion Recovery (FLAIR) MRI of the brain showing a partially empty sella (encircled).
      Fig 2
      Fig. 2Axial T2 Fast Spin Echo (FSE) MRI of the brain showing lack of optic nerve tortuosity.
      Fig 3
      Fig. 3Fundus photos consistent with bilateral grade 1 disc edema.
      Fig 4
      Fig. 4Optical coherence tomography consistent with bilateral grade 1 disc edema.
      Diagnostic studies for Rickettsial IgG and IgM antibodies were elevated at IgG 1:1024 and IgM >1:1024 specific for Rickettsia typhi, and IgG 1:64 and IgM 1:256 for Rickettsia rickettsii. The patient was thus found to be positive for Rickettsia typhi. She was treated with acetazolamide 500 mg twice a day and doxycycline 100 mg twice a day with resolution of her symptoms.

      Discussion

      Murine typhus is uncommon but the prevalence may be rising
      • Murray K.O.
      • Evert N.
      • Mayes B.
      • et al.
      Typhus group Rickettsiosis, Texas, USA, 2003–2013.
      . To our knowledge, this is only the fourth case describing papilledema and pseudotumor cerebri secondary to Rickettsia typhi infection. Although the symptoms and signs may mimic idiopathic intracranial hypertension, patients with murine typhus have symptoms that are not related to increased intracranial pressure (e.g., fever, myalgias, and constitutional symptoms) and abnormal laboratory studies (e.g., elevated acute phase reactants and liver function studies).
      Patients presenting with recurrent fever, headache, abdominal pain, and/or a rash should be evaluated for arthropod-borne illnesses, including murine typhus. Ophthalmologists should inquire about fever, rash, and stiff neck in cases of possible pseudotumor cerebri because the imaging and the cerebrospinal fluid, as in our case, can be consistent with idiopathic intracranial hypertension.

      Footnotes and Disclosures

      The authors have no proprietary or commercial interest in any materials discussed in this article.

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