The patient is a Portuguese man expatriated in Angola for seven years. He lived in the Benguela province and travelled frequently to rural regions of Huambo and Huila. Fifteen days before returning to Portugal, he went on camping in a tropical forest region of Malange, close to the Democratic Republic of Congo border.
He returned to Portugal to visit friends and relatives and after five days he experienced high fever, asthenia, dizziness and myalgia. He was diagnosed with Plasmodium falciparum malaria with 8% parasitemia (with no severity criteria according to the WHO guidelines 1). He was successfully treated with endovenous quinine-doxycycline. …show more content…
The EEG was consistent with a severe subcortical encephalopathy with no epileptic activity. Brain MRI showed a mild increase of T2/FLAIR signal in the caudate-capsule-lenticulate regions with no gadolinium enhancement. Extensive CSF and serum studies were negative for infection or systemic autoimmune causes (table).
The patient did not improve. On the 8th hospitalization day, after exclusion of the other differential diagnosis hypothesis, we assumed a clinical diagnosis of PMNS. A five-day course of 1g intravenous methylprednisolone was initiated. After the second day, the patient showed a significant clinical improvement. The CSF analysis on day 3 of corticotherapy also showed improvement: 34 cells and proteins 1,7 g/dL. The patient was discharged on day 15, with no symptoms or physical examination …show more content…
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The PMNS was first described in 1996 in Vietnam3, although there are some previous descriptions in India and Sri Lanka4, 5. The heterogeneous clinical picture is characterized by fever, behavior abnormalities and ataxic gait; the CSF shows typically lymphocytic pleocytosis with hyperproteinorrachia. The treatment is not consistently performed or consensual; the clinical course is usually benign6. No antibodies have been described in association with PMNS.
A new form of autoimmune encephalitis associated with neurexin-3alpha antibodies was recently described in 5 patients2. Comparing with those cases, our patient is the first clearly preceded by an infection. Reviewing the clinical cases described by Gresa-Arribas et al.2, one of them also had history of malaria a few months before presentation (not reported). In our patient, the clinical presentation was milder: no depressed consciousness or ICU admission necessity. The use of immunotherapy (corticosteroids or cyclophosphamide) was the mainstay of treatment, differently in the PMNS. In the few cases describing PMNS, the prognosis was good. The same is not true in neurexin-3alpha antibodies encephalitis (only one patient in five had a substantial recovery and 2 patients