Case Report of SARS-CoV-2 Misdiagnosis: West Nile Virus Meningoencephalomyelitis in Patient With SLE

west nile virus, mosquito, blood
mosquito sucking blood.
Authors presented the case of 63-year-old woman with SLE with West Nile virus meningoencephalomyelitis that was misdiagnosed as COVID-19.

A fatal case of West Nile virus (WNV) meningoencephalomyelitis – misdiagnosed as COVID-19 – was reported in an Egyptian woman with a long-standing history of systemic lupus erythematosus (SLE) and stage 4 lupus nephritis, according to a case study published in The American Journal of Tropical Medicine and Hygiene.

The 63-year-old patient presented to Luigi Sacco Hospital in Milan, Italy, after testing positive for SARS-CoV-2 RNA by real-time polymerase chain reaction (PCR; performed on a nasopharyngeal swab). She had been living in metropolitan Milan during the previous year and had not returned to Egypt since her arrival. The patient had been receiving immunosuppressive therapy with azathioprine and steroids since 1999, had a history of type 2 diabetes mellitus, and severe coronary artery disease.

One day before the COVID-19 diagnosis, the patient was admitted to the emergency department of another hospital with complaints of a 4-day history of malaise, fever, abdominal pain, and diarrhea. Blood tests revealed mild leukocytosis, thrombocytopenia, and increased serum creatinine concentrations. The patient was empirically treated with intravenous ceftriaxone (2 g/d) and transferred to the hospital.

Upon admission on August 8, 2020, the patient’s vital signs were within normal range, she did not require oxygen supplementation, and she appeared cognitively intact despite the linguistic barrier. Later, the same night, she developed confusion and agitations, which were interpreted as delirium.

The following day, the patient developed high fever (up to 39 °C) with persistent confusion. A neurology consultation suggested the presence of coarse tremors and myoclonus of the extremities; however, a computed tomography scan of the brain did not reveal intracranial abnormalities. Following lumbar puncture, cerebrospinal fluid was notable for pleocytosis, a glucose concentration of 62 mg/dL, and a protein concentration of 1080 mg/L.

Nasopharyngeal swabs for SARS-CoV-2 detection were performed on August 8, 9, and 10, all of which were negative for the viral RNA. On August 11, the patient neurologically deteriorated and was intubated and transferred to the intensive care unit (ICU). Negative PCR results for SARS-CoV-2 were suggestive of COVID-19 in a convalescent phase.

Due to worsening thrombocytopenia (47,000/µL), a second lumbar puncture was not feasible. In addition, electroencephalogram results demonstrated epileptic activity and a generalized slowing with diffuse irregular delta activity with arrhythmic waves.

A WNV virus serology and PCR on blood and urine were then requested. Immunoglobulin (Ig) M and IgG anti-WNV were positive in blood and urine samples. Following neurologic reevaluation, a diagnosis of WNV was made on August 13; however, despite supportive therapy, the patient died 6 days later in the ICU.

Authors of the case report noted that the patient could have been in the convalescent phase of COVID-19, but her rapid clinical deterioration incited concern for potential central nervous system opportunities infections and the possible onset of neuropsychiatric lupus.

“Although a diagnosis of WNV encephalitis should always be kept in mind, in our patient, the initial diagnosis of COVID-19 was misleading and, because of the imposed measures of strict hospital isolation for such patients, it may have contributed to a delayed diagnosis,” the authors wrote. “Indeed, we may speculate that if the diagnosis of WNV had not been made, our patient’s death would have been categorized as due to SARS-CoV-2.”

The authors also added that despite the increasing reports of neurologic complications associated with SARS-CoV-2 infection, it is imperative to maintain a high index of suspicion of other infections during the COVID-19 pandemic.


Schiuma M, Pezzati L, Ballone E, et al. Case report: a fatal case of west nile virus meningoencephalomyelitis in a woman with systemic lupus erythematosus initially misdiagnosed as SARS-CoV-2 infection. Am J Trop Med Hyg. Published online March 29, 2021. doi:10.4269/ajtmh.21-0041