Red flags for suspecting anti-NMDAr encephalitis in a first psychotic episode: report of two cases. / Banderas rojas para sospechar encefalitis anti-NMDAr en un primer episodio psicótico: reporte de dos casos.

Anti-N-methyl-D-Aspartate receptor (NMDAr) encephalitis is a recently described clinical entity with an increasing number of reported cases. Psychiatric symptoms in the early stages of the disease constitute a diagnostic challenge for the treating physician. We present two clinical cases: clinical case 1, a 26-year-old man, and clinical case 2, an 18-year-old man; both presented with a first episode of psychosis and were hospitalized as psychiatric disorders. Subsequently, both cases were diagnosed as anti-NMDAr encephalitis. The high prevalence of psychiatric symptoms in anti-NMDAr encephalitis forces psychiatrists and neurologists to have a high degree of suspicion in the presence of atypical symptoms in patients evaluated for the first episode of psychosis.