Murine typhus presenting as subacute meningoencephalitis

Typhus group Rickettsia community-acquired bacterial central nervous system infections: We must think outside the box!

Typhus group rickettsiosis (TGR), caused by Rickettsia typhi and Rickettsia prowazekii, are globally distributed vector-borne diseases with increasing cases. Diagnosis is usually clinical, confirmed by seroconversion of IgG antibodies. Human infection occurs in diverse geographic areas with some developing CNS infection characterized by fever, headache, meningismus, and/or focal signs - usually beyond the first week of initial symptomatology. Seizures and other CNS manifestations have been observed. When untreated, infection may result in neurologic sequelae and even death. This study presents a systematic review of all documented cases of Rickettsia typhi meningoencephalitis published since 2015 with the addition of five cases of TGR in South Coastal Texas, USA. This review followed the guidelines outlined in PRISMA. A schematic explanation of the pathophysiology is offered. CSF may present with high opening pressure, mild to moderate pleocytosis, mildly elevated protein levels, and low csf/serum glucose ratio, or normal findings. Meningeal enhancement, intracranial hypertension, and focal abnormalities have been described in imaging studies, but can be normal. Treatment with doxycycline leads to prompt resolution of symptoms. Failure to initiate early empiric treatment can lead to serious consequences. The study recommends routine testing for TGR in patients from endemic areas with classical symptoms when other diagnoses are inconclusive or in cases with atypical presentations. The authors advocate for incorporating empiric treatment for murine typhus into community-acquired bacterial meningitis guidelines in endemic areas; and stress the importance of enhancing laboratory diagnostic capabilities in public health entities world-wide. Further studies of community acquired mengingoencephalitis caused by TGR are highly encouraged.

A case series of Mediterranean spotted fever and murine typhus with neurological manifestations

BACKGROUND OBJECTIVES

Severe cases with neurological manifestations of rickettsiosis have been reported. We aimed to identify the epidemiological, clinical and laboratory features of central nervous system rickettsial infections and to describe the treatment.

METHODS

We carried out a retrospective study that included all patients hospitalized with rickettsiosis in the infectious diseases department of Hedi Chaker University Hospital in Sfax, Tunisia between 1993 and 2018.

RESULTS

We identified 47 patients with central nervous system rickettsial infections among 440 patients with rickettsial infections (10.7%). Skin rash (31.9% vs 87.8%; p<0.001) and eschar (4.2% vs 27.7%; p<0.001) were less frequent among patients with central nervous system rickettsial infections. Complications (6.4% vs 0.5%; p=0.01) and death (4.2% vs 0.3%; p=0.03) were more frequent among patients with central nervous system rickettsial infections.

INTERPRETATION CONCLUSION

Cardinal clinical features and typical laboratory results including thrombocytopenia were less frequent, and prognosis was more severe in patients with central nervous system rickettsial infections.

Zoonotic Disease Testing Practices in Pediatric Patients with Meningitis and Encephalitis in a Subtropical Region

Emerging vector-borne and zoonotic pathogens can cause neuroinvasive disease in children; utilization of appropriate diagnostic testing can be low, hindering diagnosis and clinical management of these cases. We must understand factors that influence healthcare providers’ decisions to order diagnostic testing. We reviewed medical charts for pediatric meningitis and encephalitis patients (90 days–18 years) between 2010 and 2017 and analyzed variables associated with testing for known neuroinvasive zoonotic pathogens in the southern United States: West Nile virus (WNV), Bartonella spp., and Rickettsia spp. Among 620 cases of meningitis and encephalitis, ~1/3 (n = 209, 34%) were tested for WNV. Fewer cases were tested for Bartonella (n = 77, 12%) and Rickettsia (n = 47, 8%). Among those tested, 14 (7%) WNV, 7 (9%) Bartonella, and 6 (13%) Rickettsia cases were identified. Factors predicting testing were similar between all agents: clinical presentation of encephalitis, focal neurologic symptoms, new onset seizure, and decreased Glasgow Coma Scale on admission. Cases with a history of arthropod contact were more likely to be tested; however, we did not see an increase in testing during the summer season, when vector exposure typically increases. While our test utilization was higher than that reported in other studies, improvement is needed to identify zoonotic causes of neuroinvasive diseases.

Abducens nerve palsy with associated retinal involvement secondary to rickettsia typhi infection

OBJECTIVE

To report a case of abducens nerve palsy with associated retinal involvement due to rickettsia typhi infection.

MATERIAL AND METHODS

A single case report documented with multimodal imaging.

RESULTS

A 18-year-old woman with a history of high-grade fever was initially diagnosed with typhoid fever and treated with fluoroquinolone. She presented with a 5-day history of diplopia and headaches. Her best-corrected visual acuity was 20/20 in both eyes. Ocular motility examination showed left lateral gaze restriction. Lancaster test confirmed the presence of left abducens palsy. Fundus examination showed optic disc swelling in both eyes associated with superotemporal retinal hemorrhage and a small retinal infiltrate with retinal hemorrhage in the nasal periphery in the left eye. Magnetic resonance imaging (MRI) of the brain and orbits showed no abnormalities. A diagnosis of rickettsial disease was suspected and the serologic test for Richettsia Typhi was positive. The patient was treated with doxycycline (100 mg every 12 h) for 15 days with complete recovery of the left lateral rectus motility and resolution of optic disc swelling, retinal hemorrhages, and retinal infiltrate.

CONCLUSION

Rickettsial disease should be considered in the differential diagnosis of abducens nerve palsy in any patient with unexplained fever from endemic area. Fundus examination may help establish an early diagnosis and to start an appropriate rickettsial treatment.

Two cases of uveitis associated with severe transaminitis during a Rickettsia typhi outbreak in Los Angeles County

Purpose

To report the clinical presentation, multimodal imaging, and management of two patients with Rickettsia typhi infection who presented with transaminitis and bilateral uveitis.

Observations

We report two cases of murine typhus-associated uveitis in the setting of a Rickettsia typhi outbreak in Los Angeles County. In case 1, a 29-year-old Hispanic female presented with scotoma of the right eye and bilateral floaters after 2 weeks of persistent fevers, maculopapular rash, and arthralgia. Clinical examination and optical coherence tomography (OCT) revealed vitreous cell and scattered white spots in both eyes at the level of the inner retina, and a cotton wool spot inferiorly in the left eye. Multiple hyperautofluorescent spots were seen on widefield fundus autofluorescence (FAF). Retinal vascular leakage and optic disc hyperfluorescence were visualized on widefield fluorescein angiography (FA). These findings were concerning for a white dot syndrome (WDS). The patient was started on oral prednisone 30 mg daily. Serologic testing during the convalescent phase returned positive for R. typhi infection and she was started on doxycycline. 3 weeks later, she reported complete resolution of scotoma and significant improvement of bilateral floaters.

In the second case, a 42-year-old Hispanic male presented with sudden bilateral increased floaters and blurry vision after 12 days of persistent fever and headache. Clinical examination revealed trace flare with 1+ cell in the anterior chamber, 1+ vitreous cell, and multiple white dots in both eyes at the level of the inner retina. FAF showed scattered hyperautofluorescent spots in both eyes. FA demonstrated late retinal vascular leakage with bilateral hyperfluorescent optic discs. He was started on oral prednisone 40mg, prednisolone acetate 1% drops, and cyclopentolate 1% drops daily. 2 weeks later, serologic titers returned positive for murine typhus and he was started on doxycycline with gradual taper off of steroids. He subsequently had complete resolution of floaters, blurry vision, and the inner retinal white spots.

Conclusions and Importance

Murine typhus-associated uveitis may present with scotoma and increased floaters in the setting of persistent fevers and transaminitis, with pre- or inner retinal white spots seen on fundus examination. Ophthalmologists may aid in prompt diagnosis and initiation of antibiotic therapy, which can shorten the course of the disease and in turn, reduce the risk of severe complications.

Rickettsia typhi central nervous system infection

A 39 year-old male was residing along the south coast of Texas, the USA, presented with fever, myalgias, headaches, and weight loss for ten days. Symptoms and manifestations progressed to include nuchal rigidity, photophobia, hyponatremia, thrombocytopenia, and transaminitis despite the intravenous administration of ceftriaxone and azithromycin. A lumbar puncture performed in the Emergency Department yielded pleocytosis and glucose cerebrospinal fluid/serum ratio of 0.35, suggestive of meningoencephalitis. Conglomerate data raised the suspicion of meningitis secondary to a zoonotic acquired infection, which was later confirmed to be Rickettsia typhi. Doxycycline is the drug of choice for the suspected Rickettsia disease. After doxycycline administration, the patient improved and was discharged home asymptomatic.

Murine typhus presenting with status epilepticus

Patients with rickettsial infection usually present with a febrile illness, headache, arthromyalgia and various biochemical abnormalities. Neurologic involvement is rare in murine typhus. Here, we report a case of a patient who presented with status epilepticus secondary to Rickettsia typhi infection.

Case of Rickettsia typhi-induced Brain Abscess Mimicking Brain Tumor

Murine typhus is one of the most prevalent rickettsial infections in the world, caused by the bacterial genus Rickettsia. Though the disease manifests a relatively benign clinical course with fever, rash, and headache being the 3 classic symptoms, neurological complications may arise in patients that could become permanent. In this case study, a patient with a brain abscess caused by R typhi infection is described. Based upon the recent reemergence of arthropod-borne disease, the findings in this case are significant; R typhi can cause a brain abscess that mimics a brain tumor, which delays the diagnosis and appropriate management of the disease. Murine typhus should always be considered when performing the differential diagnosis of brain abscesses in South Korea.

Case Report: Fulminant Murine Typhus Presenting with Status Epilepticus and Multi-Organ Failure: an Autopsy Case and a Review of the Neurologic Presentations of Murine Typhus

Murine typhus (MT) is an important cause of febrile illness in endemic areas, and there is an epidemiologic resurgence of this infection currently transpiring in Texas and California. Fatal cases and severe neurological complications are rare. A fatal case of MT in a middle-aged man is reported with a course culminating in multi-organ failure and refractory status epilepticus. An autopsy revealed hemorrhagic pneumonia, acute tubular necrosis, and ischemic necrosis in the liver, adrenals, and brain. We have also reviewed the neurologic complications of MT.

Infectious encephalitis: Management without etiological diagnosis 48hours after onset

Introduction

The etiological diagnosis of infectious encephalitis is often not established 48 hours after onset. We aimed to review existing literature data before providing management guidelines.

Method

We performed a literature search on PubMed using filters such as “since 01/01/2000”, “human”, “adults”, “English or French”, and “clinical trial/review/guidelines”. We also used the Mesh search terms “encephalitis/therapy” and “encephalitis/diagnosis”.

Results

With Mesh search terms “encephalitis/therapy” and “encephalitis/diagnosis”, we retrieved 223 and 258 articles, respectively. With search terms “encephalitis and corticosteroid”, we identified 38 articles, and with “encephalitis and doxycycline” without the above-mentioned filters we identified 85 articles. A total of 210 articles were included in the analysis.

Discussion

Etiological investigations must focus on recent travels, animal exposures, age, immunodeficiency, neurological damage characteristics, and potential extra-neurological signs. The interest of a diagnosis of encephalitis for which there is no specific treatment is also to discontinue any empirical treatments initially prescribed. Physicians must consider and search for autoimmune encephalitis.

Persisting Rickettsia typhi Causes Fatal Central Nervous System Inflammation

Rickettsioses are emerging febrile diseases caused by obligate intracellular bacteria belonging to the family Rickettsiaceae. Rickettsia typhi belongs to the typhus group (TG) of this family and is the causative agent of endemic typhus, a disease that can be fatal. In the present study, we analyzed the course of R. typhi infection in C57BL/6 RAG1(-/-) mice. Although these mice lack adaptive immunity, they developed only mild and temporary symptoms of disease and survived R. typhi infection for a long period of time. To our surprise, 3 to 4 months after infection, C57BL/6 RAG1(-/-) mice suddenly developed lethal neurological disorders. Analysis of these mice at the time of death revealed high bacterial loads, predominantly in the brain. This was accompanied by a massive expansion of microglia and by neuronal cell death. Furthermore, high numbers of infiltrating CD11b(+) macrophages were detectable in the brain. In contrast to the microglia, these cells harbored R. typhi and showed an inflammatory phenotype, as indicated by inducible nitric oxide synthase (iNOS) expression, which was not observed in the periphery. Having shown that R. typhi persists in immunocompromised mice, we finally asked whether the bacteria are also able to persist in resistant C57BL/6 and BALB/c wild-type mice. Indeed, R. typhi could be recultivated from lung, spleen, and brain tissues from both strains even up to 1 year after infection. This is the first report demonstrating persistence and reappearance of R. typhi, mainly restricted to the central nervous system in immunocompromised mice.

Abducens nerve palsy and meningitis by Rickettsia typhi

Patients with rickettsial infection may present with encephalitis or meningitis but neurologic involvement is rare in murine typhus. Here, we report two patients with Rickettsia typhi meningitis who presented with cranial neuropathy, presumably caused by two distinct disease processes. Recognition of the disease manifestations is important because rickettsial infections are potentially associated with significant morbidity. Simple effective treatments are available.

Murine typhus in southern Taiwan during 1992-2009

Clinical information regarding murine typhus in Taiwan is limited. In this study, 81 cases of serologically documented murine typhus during 1992-2009 at four referral hospitals in southern Taiwan were analyzed. There was a significant correlation between average environmental temperature and case numbers of murine typhus (r = 0.747, P = 0.005). Acute hepatitis was found in 67% of cases, and hyperbilirubinemia (serum total bilirubin ≥ 23.9 μmol/L) was found in 38%. The intervals between the initiation of appropriate therapy to defervescence were longer in patients with hyperbilirubinemia than those without hyperbilirubinemia (6.1 versus 4.1 days; P = 0.015). Nine (11.1%) showed development of severe illnesses such as acute respiratory distress syndrome (2 patients), aseptic meningitis (3), and acute renal failure (4). Only one died of acute respiratory distress syndrome. Cases of murine typhus were often found during the summer and had acute febrile hepatitis. Those patients with hyperbilirubinemia tended to have a delayed recovery even with appropriate therapy.

Murine typhus in central Greece: epidemiological, clinical, laboratory, and therapeutic-response features of 90 cases

OBJECTIVES

To document and evaluate the clinico-epidemiological profile of murine typhus during the re-emergence of the disease in a previously endemic focus in central Greece.

METHODS

This was a 5-year, hospital-based, observational study, in which 90 adult patients with murine typhus were prospectively identified and studied.

RESULTS

Most cases of the disease occurred in rural (52%) and semi-urban (34%) settings, with a seasonal frequency peak during the late summer. The triad of fever, headache, and rash was present in 64% of the patients within 2 days of hospital admission. Normal white blood cell counts (63%), thrombocytopenia (81%), and a high erythrocyte sedimentation rate (93%) were the main hematological findings upon presentation. Elevated aminotransferases (>84%), hypoalbuminemia (81%), and hyponatremia (36%) were prominent biochemical abnormalities. Pulmonary, neurological, and renal complications were noted in 26% of the patients and subsided after specific treatment. The duration of fever was shorter in patients treated with doxycycline (median 3 days) compared to ofloxacin (p=0.001) or doxycycline plus ofloxacin (p=0.009).

CONCLUSIONS

Murine typhus has the potential to cause significant morbidity. Awareness of the disease in endemic areas, early recognition of its clinical and laboratory features, and prompt administration of effective treatment are key factors to prevent potentially severe complications.

Reversible hearing impairment: delayed complication of murine typhus or adverse reaction to azithromycin?

Delayed and reversible hearing loss occurred in a 55-year-old male patient with murine typhus infection. The patient had the initial symptoms of headache, fever and chills, followed by the occurrence of bilateral hearing loss on day 9 from fever onset. Murine typhus was diagnosed with a high IgM titre by indirect immunofluorescence assay. After treatment with azithromycin and prednisolone, the fever and other symptoms subsided gradually and bilateral hearing loss improved 3 weeks later. Though an adverse reaction to azithromycin could not be ruled out, delayed onset of hearing loss was more likely a complication of murine typhus, mainly because the hearing loss did not occur during the azithromycin usage period. Although hearing loss due to murine typhus is rare, clinicians should be alert to the existence of such a delayed complication.

Rickettsial and ehrlichial infections

Rickettsial diseases represent a clinically homogeneous group of infections characterized by fever, headache myalgias, variable presence of a rash, and a broad spectrum of neurological manifestations. Epidemiological information including time of year, geography, history of arthropod exposure, and animal contact gives important clues to the diagnosis, and should be actively elicited. Abnormalities in hematological indices of liver function tests should also increase suspicion for illness. Delay in initiation of doxycycline therapy while awaiting laboratory confirmation of infection has been associated with progressive neurological impairment and death. Clinicians should maintain a low threshold to initiate empiric therapy for rickettsial diseases in any patient with neurological findings and compatible exposures, signs, or laboratories, as these syndromes represent readily treatable causes of neurological dysfunction.

Facial Paralysis and Meningitis Caused by Rickettsia typhi infection

Involvement of cranial nerves was rarely reported in various rickettsioses. We present here for the first time a case of peripheral facial paralysis associated with Rickettsia typhi infection.

Murine typhus: an unrecognized suburban vectorborne disease

Murine typhus, an acute febrile illness caused by Rickettsia typhi, is distributed worldwide. Mainly transmitted by the fleas of rodents, it is associated with cities and ports where urban rats (Rattus rattus and Rattus norvegicus) are abundant. In the United States, cases are concentrated in suburban areas of Texas and California. Contrary to the classic rat-flea-rat cycle, the most important reservoirs of infection in these areas are opossums and cats. The cat flea, Ctenocephalides felis, has been identified as the principal vector. In Texas, murine typhus cases occur in spring and summer, whereas, in California, cases have been documented in summer and fall. Most patients present with fever, and many have rash and headache. Serologic testing with the indirect immunofluorescence assay is the preferred diagnostic method. Doxycycline is the antibiotic of choice and has been shown to shorten the course of illness.

Méningite révélant une infection à Rickettsia typhi

INTRODUCTION

Neurological manifestations are rarely observed in murine typhus. We present a case of meningitis caused by Rickettsia typhi.

EXEGESIS

We report a case of Tunisian 57-year-old woman admitted for suspicion of meningitis. Clinical examination revealed fever at 39,5 degrees C and nuchal rigidity. There were no focal neurologic signs, cutaneous rash or eschar. Lumbar puncture showed clear cerebrospinal fluid containing normal glucose, 0,48 g/l protein and 30 WBC (78% lymphocyte). Gram-stained smear and culture were negative. Serology confirmed the diagnosis. The patient was initially treated by ampicillin 12 g daily but remained febrile. Retinal lesions were detected on ophthalmic examination, suggesting rickettsial infection. Clinical outcome was good after 7-day treatment with oral ciprofloxacin 1,5 g daily. The mean follow-up was six months.

CONCLUSION

Murine typhus is an endemic zoonosis. Neurological manifestations were uncommon. An ophthalmic examination is recommended if rickettsiosis was suspected.

Sub-acute neuropathy in patients with African tick bite fever

African tick bite fever (ATBF) caused by Rickettsia africae is an emerging health problem in travellers to sub-Saharan Africa. We here present 6 patients with evidence of long-lasting sub-acute neuropathy following ATBF contracted during safari trips to southern Africa. Three patients developed radiating pain, paresthaesia and/or motor weakness of extremities, 2 had hemi-facial pain and paresthaesia, and 1 developed unilateral sensorineural hearing loss. When evaluated 3-26 months after symptom onset, cerebrospinal fluid samples from 5 patients were negative for R. africae PCR and serology, but revealed elevated protein content in 3 and mild pleocytosis in 1 case. Despite extensive investigations, no plausible alternative causes of neuropathy could be identified. Treatment with doxycycline in 2 patients had no clinical effect. Given the current increase of international safari tourism to sub-Saharan Africa, more cases of sub-acute neuropathy following ATBF may well be encountered in Europe and elsewhere in the y to come.

Rickettsia typhi infection presenting as subacute meningitis

We report two children with Rickettsia typhi infection presenting with mild central nervous system manifestations and pleocytosis in cerebrospinal fluid. Murine typhus should be included in the differential diagnosis of meningoencephalitis in children who are residents of endemic areas.

Murine typhus in South Texas children

BACKGROUND

Murine typhus is a zoonotic infection caused by Rickettsia typhi. This illness used to be endemic in the southeastern and gulf coast of the United States and is now only rarely reported in South Texas and Southern California. Murine typhus causes a febrile illness with headache and rash that has been well-described in adults.

OBJECTIVE

To define the epidemiologic and clinical characteristics, laboratory findings, hospital course and response to therapy of children discharged from our hospital with a diagnosis of murine typhus.

METHODS

Retrospective chart review of all children discharged from Driscoll Children's Hospital, Corpus Christi, TX, from January 1, 1990, to June 30, 1998, with a diagnosis of murine typhus. Patients. Thirty children (17 females) ages 2 to 17 years (mean, 10 +/- 4 years).

RESULTS

Eighty percent of the children were admitted between May and November, and 67% had a history of contact with or exposure to a potential animal reservoir. Children were admitted after a mean of 7 +/- 4 days. The most common clinical features were fever 100%, rash 80% and headache 77%. Laboratory abnormalities included elevated erythrocyte sedimentation rate (75%), elevated serum transaminases (67%), hyponatremia (66%) and increased immature leukocytes without leukocytosis (63%). Only one child had leukocytosis and 40% had leukopenia. Defervescence occurred a mean of 35 +/- 19 h after initiation of appropriate antibiotics. Hospitalization lasted for a mean of 7 +/- 3 days. There were no readmissions and no patients died as a result of the infection.

CONCLUSIONS

Despite being rarely reported in this country now, murine typhus continues to be an important cause of fever and hospitalization for children in South Texas. Children with murine typhus develop an illness similar to that reported in adults with fever, rash and headache. Children respond quickly to therapy with doxycycline or tetracycline and recover completely from their illness.