Ramírez-Bermúdez J,Trejo-Marquez H, Manterola O, Soto-Hernández JL

Language: Spanish
References: 7
Page: 8-11
PDF size: 546.13 Kb.

ABSTRACT

Some patients admitted due to psychotic symptoms and diagnosed as schizophrenic or bipolar first episode, present in fact acute encephalitis. Objective: to identify the frequency of two diagnostic errors in patients with acute encephalitis and/or psychotic disorders: type I error, or false positive (in a subject without brain infection a lumbar puncture is made), and type II error, or false negative (a subject without brain infection is not recognized and lumbar puncture is delayed). Patients and methods: a retrospective, observational study with clinic files audit was done in cases attended between 1990-2005 at a neurological institution, WITH diagnosis of acute encephalitis or first psychotic episode (without infection). Results: 125 cases of acute encephalitis and 104 cases of first psychotic episode were included. Type I error (false positive) was observed in 46% of the pure psychotic subjects. Type II error (false negative) was observed in 26% of subjects with encephalitis, most of them attended in other psychiatric hospitals, with development of medical complications. Most subjects with encephalitis meet criteria for a DSM-IV psychiatric diagnosis: delirium (68%), psychotic disorder (8.8%), impulse control disorder (5.6%), catatonia (3.2), sleep disorder (1.6%). Conclusions: diagnostic errors are common in the differential diagnosis between first onset primary psychotic disorders, and acute encephalitis, probably due to the high frequency of mental disorders in subjects with brain infections. There is a lack of precise clinical criteria for the indication of lumbar puncture in subjects with acute mental disturbances.

REFERENCES

1. Wise TN, Le Buffefp, Granger SI. Meningoencephalitis presenting as an acute paranoia psychosis. Internacional Journal of Psychiatry in Medicine 1977-1978;8:405-14.

2. Ramirez-Bermudez J, Soto-Hernández JL, López-Gómez M, Mendoza-Silva M, Colin-Piana R, Campillo-Serrano C. Frequency of neuropsychiatric signs and symptoms in patients with viral encephalitis. Rev Neurol 2005; 41: 140-4.

3. Wilson LG: Viral encephalopathy mimicking funtional psychosis. Am J Psychiatry 1976;133:165-70.

4. Frasca J, Kilpatric TJ, Burns RJ: Protracted forms of encephalitis with good outcome. Medical Journal of Australia 1993;158:629-30.

5. Srikanth S, Raui, Poornima KS, Shetty KT, et al. Viral antibodies in recent onset, non organic psychoses: correspondence with symptomatic severity. Biol Psychiatry 1994; 36: 517-21.

6. Ramírez-Bermúdez J, López-Gómez M, Sosa AL, Aceves S, Nader- Kawachi J, Nicolini H. Frequency of Delirium in a Neurological Emergency Room. J Neuropsychiatry Clin Neurosci 2006;18:108- 12

7. Serrano-Duenas M. Neuroleptic malignant syndrome in patients with non-herpetic viral encephalitis. Study of 7 cases. Med Clin 2002;118(2):62-4.