Most of the literature regarding the importance of accurately and efficiently differentiating neuropsychiatric symptoms as secondary to medical conditions or as a primary psychiatric illnesses is found in the emergency department setting. It has been reported that 6 to 12% of patients presenting to the emergency department have psychiatric complaints or behavioral disturbances.1,2 Patients with psychiatric or behavioral disturbances are generally “medically cleared” prior to transfer to psychiatric care.2 Assessing if a patient is “medically cleared” helps to identify medical illnesses that could cause or contribute to psychiatric or behavioral symptoms which may make treatment at a psychiatric facility inappropriate or even dangerous.2 Appropriate treatment in the emergency department setting, therefore, may prevent morbidity and mortality associated with misdiagnosing of a medical illness as a psychiatric illness and from improper treatment of psychiatric illnesses.2 When psychiatric, neurologic, or behavioral manifestations are secondary to medical conditions, the focus of treatment should be on the underlying condition.3 This can be said for any kind of signs or symptoms – rarely is a single or set of signs or symptoms addressed without an evaluation for the underlying root cause. Symptomatic treatment of the neuropsychiatric manifestations, however, should not be overlooked and should run parallel to the primary condition.3 

To help identify a primary psychiatric illness compared to symptoms secondary to a medical illness, several factors that may assist in clarifying diagnosis include a focus on cognitive versus somatic symptoms, identification of personal or family history of psychiatric illness and response to treatment, careful neurologic exam emphasizing cognitive and mental status exam as part of the physical exam, and an understanding that a psychiatric diagnosis is not purely a diagnosis of exclusion of medical illnesses.3 Features suggesting that psychiatric symptoms are secondary to a medical illness include an abrupt onset with no known or readily recognizable precipitants, a temporal association with onset, worsening, or remission of the psychiatric symptoms concurrent with the medical illness, and the presence of atypical features.3,4 Additionally, the absence of a personal or family history of psychiatric diagnosis, late onset of new behavioral symptoms, obvious systemic disease, evidence of increased intracranial pressure, nonauditory hallucinations, use of psychoactive or centrally-acting medications, the occurrence of autonomic dysfunction with good premorbid function, and treatment resistance further suggest a medical origin.4 Though routine laboratory testing of all psychiatric patients presenting to the emergency department has not been supported in the literature, it is suggested that a complete history (including a detailed medication history) and physical exam with a full set of vital signs may be sufficient to exclude medical reasons for symptom presentation.1,2,5 Further laboratory and ancillary testing may be guided by the obtained information.1,2,5 Obtaining information directly from the patient may be, at times, difficult to obtain, therefore, collateral history from bystanders, family, friends, caregivers, health care professionals, law enforcement, paramedics, etc. is important.2 

Illnesses that may be commonly known to be associated with psychiatric symptoms are presented in Table 1. Increasing awareness and understanding of neuropsychiatric symptoms and adverse effects (and subsequently, management) may lead to more appropriate therapy choices or management and improved patient care. Additionally, comorbid medical illnesses may have implications on psychotropic medication selection. This issue of the Mental Health Clinician highlights psychiatric and neurologic manifestations of medical illnesses or those adverse effects secondary to medications.

Table 1.

Medical illness considerations in psychiatric diagnoses

Medical illness considerations in psychiatric diagnoses
Medical illness considerations in psychiatric diagnoses
1.
Szpakowicz
M
,
Herd
A.
“Medically cleared”: how well are patients with psychiatric presentations examined by emergency physicians?
.
J Emerg Med
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2008
;
35
(
4
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369
72
. .
2.
Sood
TR
,
Mcstay
CM.
Evaluation of the psychiatric patient
.
Emerg Med Clin N Am
.
2009
;
27
(
4
):
669
83
,
ix
. .
3.
O' Brien
RF
,
Kifuji
K
,
Summergrad
P.
Medical conditions and psychiatric manifestations
.
Adolesc Med
.
2006
;
17
:
49
77
.
4.
Talbot-Stern
JK
,
Green
T
,
Royle
TJ.
Psychiatric manifestations of systemic illness
.
Emerg Med Clin North Am
.
2000
;
18
(
2
):
199
209
,
vii
viii
.
PubMed PMID: 10767878
.
5.
Janiak
BD
,
Atteberry
S.
Medical clearance of the psychiatric patient in the emergency department
.
J Emerg Med
.
2012
;
43
(
5
):
866
70
. .