Misdiagnosis Problems

Based on some of the discussions about allergies, nutrient deficiencies, et cetera causing schizophrenia, I thought that this list of medical conditions that cause or are associated with schizophrenia-like symptoms might be interesting. Individuals suffering psychotic symptoms as a result of these should most likely not be classified as suffering from schizophrenia; rather, the diagnosis should probably be Psychotic Disorder Due to a General Medical Condition and the patient treated accordingly. This is part of the differential diagnosis. You can imagine the problem if the physician misdiagnoses the illness based only on the symptoms. The problem is compounded when a family member concludes, for example, that megavitamin therapy is the solution for schizophrenia because their loved one suffered psychosis because of a vitamin B12 deficiency and the doctor diagnosed schizophrenia without checking alternatives. Not only does this add to the anecdotal confusion about schizophrenia, it adds to the suffering of all concerned because of a misdiagnosis.

Bob

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Differential Diagnosis of Schizophrenialike Symptoms

Medical or neurological Substance-induced psychotic disorder, especially amphetamines, alcohol hallucinosis, anticholinergic, barbiturate withdrawal, belladonna alkaloids, cimetidine, cocaine, digitalis, disulfiram, hallucinogens, L-dopa, phencyclidine (PCP) Epilepsy, especially of temporal lobe origin Tumors, expecially frontal or limbin CNS infections, especially herpes encephalitis, Creuzfeldt-Jacob disease, neurosyphilis, AIDS Acute intermittent porphyia Dementia of the Alzheimer's type B12 deficiency Carbon monoxide poisoning Endocrinopathies, aspecially adrenal and thyroid Fabry's disease Fahr's syndrome Hallervorden-Spatz disease Heavy metal poisoning (arsenic, manganese, mercury, thallium) Homocystinuria Huntington's disease Metachromatic leukodystrophy Normal-preassure hydrocephalus Pellagra Pick's disease Systemic lupus erythematosus Wernicke-Korsakoff syndrome Wilson's disease

Psychiatric Malingering Factitious disorder with predominantly psychologicl symptoms Autistic disorder Schizophrenia Schizophreniform disorder Brief psychotic disorder Mood disorder Schizoaffective disorder Psychotic disorder NOS (atypical psychosis) Delusional disorder Personality disorder, especially schizotypal, schizoid, borderline, paranoid Obsessive-compulsive disorder

Diseases and Disorders that Imitate Schizophrenia

Brain Injury or Disease Embolism Aqueductal stenosis Ischemia Trauma Tumor Epilepsy Encephalitis Narcolepsy Obstructive hydrocephalus Cerebrovascular infarction Neoplasms

Metabolic or Systemic Disorders Vitamin B12 deficiency Acquired immune deficiency system Syphilis Tuberculous meningitis Pellagra Hypoglycemia Hepatic encephalopathy Hyperthyroidism Lead poisoning Lupus erythematosus Multiple sclerosis Uremia Cotard's syndrome Herpetic encephalitis Cysticerosis Cushing's disease

Genetic or Chromosomal Disorders XXY karyotype (Klinefelter's syndrome) XO karyotype (Turner's or Noonan's syndrome) 18q- deletion (missing piece of long arm of chromosome 18) 5, q11-q13 triplication Huntington's disease Acute intermittent porphyria Metachromatic leukodystrophy Familial basal ganglia calcification Homocystinuria Phenylketonuria Wilson's diseas Albinism Congenital adrenal hyperplasia Glucose-6-phosphate dehydrogenase deficiency (favism) Kartagener's syndrome

DSM-IV Diagnostic Critera for Psychotic Disorder Due to a General Medical Condition

A. Prominent hallucinations or delusions.
B. There is evidence from the history, physical examination, or laboratory findings that the disturbance is the direct physiological consequence of a general medical condition.
C. The disturbance is not better accounted for by another mental disorder.
D. The disturbance does not occur exclusively during the course of a delirium. Code based on predominant symptom: With delusions: if delusions are the predominant symptom With hellucinations: if hallucinations are the predominant symptom

Coding note: Include the name of the general medical condition on Axis I, e.g., psychotic disorder due to malignant lung neoplasm with delusions; also code the general medical condition on Axis III. Coding note: If delusions are part of a preexisting dementia, indicate the delusions by coding the appropriate subtype of the dementia if one is available, e.g., dementia of the alzheimer's type, with late onset, with delusions.

Excerpt From Harold I. Kaplan and Benjamin J. Sadock, eds., Comprehensive Textbook of Psychiatry, 6th edition (Baltimore: Williams & Wilkins, 1995).