Psychiatric disorders organic

Dose-relation collateral effect Time-course intermediate or delayed Susceptibility factors pre-existing psychiatric disorders, organic brain injury, or addictive behavior... 

Psychogenic dysfunction occurs if a patient does not respond to psychic arousal. It occurs in up to 30% of all cases of ED. Common causes include performance anxiety, strained relationships, lack of sexual arousability, and overt psychiatric disorders such as depression and schizophrenia.5 It is postulated that the anxious or nervous man will have excessive stimulation of the sympathetic system, leading to smooth muscle contraction of arterioles and vascular spaces within erectile tissue.6 O Many patients may initially have organic dysfunction, but develop a psychogenic component as they try to cope with their inability to achieve an erection. It has been estimated that up to 80% of ED cases have an organic cause, with many having a psychogenic component as well.1... 

The differential diagnosis of depression is organized along both symptomatic and causative lines. Symptomatically, major depression is differentiated from other disorders by its clinical presentation or its long-term history. This is, of course, the primary means of distinguishing psychiatric disorders in DSM-1V. The symptomatic differential of major depression includes other mood disorders such as dysthymic disorder and bipolar disorder, other disorders that frequently manifest depressed mood including schizoaffective disorder, schizophrenia, dementia, adjustment disorder, and post-traumatic stress disorder, and, finally, other nonpsychiatric conditions that resemble depression such as bereavement and medical illnesses like cancer or AIDS. 

Indications include a wide variety of psychiatric disorders, in the first place schizophrenia, organic psychoses and other acute psychotic illnesses. However they are also of use for the manic phase of bipolar affective disorder and for psychotic depression. Under antipsychotic drug therapy patients become less agitated and restless, withdrawn and autistic patients may become more communicative, aggressive and impulsive behavior diminishes and hallucinations and disordered thinking disappear. 

Information processing in the human brain via neuro-chemically defined neuronal systems is complex. Therefore, it remains a challenge to conceptualize psychiatric disorders and their treatment in a reductionistic framework of chemical neuroanatomy. We can nonetheless broadly state that the anatomic organization of neurotransmitter systems determines their behavioral affiliation, and that receptors modulate the electrical or biochemical properties of neurons, with direct relevance to the mechanism of action of psychotropic drugs. Future research will provide more detailed information on the subtypes of neurons and specific neurotransmitters systems that are abnormal in psychiatric disorders, and provide a more rational approach to the development of new treatment interventions. 

The spectrum of clinical manifestations of organic mental disorders consists of two main clusters. The first includes the decline in the various cognitive functions (e.g., attention, memory, abstract thinking, judgment). The second cluster is related to symptoms that are found in other psychiatric disorders and that also appear in patients with organic mental disorders. Table 32-1 shows organic mental disorders included in sections F00-F09 of ICD-10. 

Computerized tomography (CT) is used in the clinical setting primarily to rule out organic lesions that might underlie or contribute to a psychiatric disorder. Specific indications may include ... 

Psychiatric disorders caused by a medical condition (e.g., acquired immune deficiency syndrome [AIDS] organic delusional disorders)... 

Complicated mania is an elaboration on the theme of the secondary type and is defined as the presence of antecedent or coexisting nonaffective psychiatric disorders and/or serious medical disorders ( 34). These patients can be grouped into psychiatric or medical cluster patients. The psychiatric cluster patients have had fewer prior psychiatric hospitalizations, an earlier onset of illness, and a history of prior suicide attempts. This contrasts with the medical cluster, which has a later age of onset, no prior history of suicide attempts, more organic features, and more deaths during the follow-up period. 

Anxiety is characterized by fear and apprehension that may or may not be associated with a cieariy identifiabie stimuius. Anxiety is a common reaction to significant life stress, is seen in conjunction with almost every psychiatric disorder, and is a common component of numerous organic disorders as well (e.g., hyperthyroidism, hypoglycemia, pheochromocytoma, complex partial seizures, pulmonary disorders, acute myocardial infarction, caffeine intoxication, various substances of abuse). Anxiety is almost invariably accompanied by physical symptoms such as the following ... 

Proper diagnosis, important with any illness, is even more crucial in treatment planning for patients with a dual diagnosis. Because psychoactive substance use can obfuscate the diagnosis, special care must be taken to preclude organically based syndromes. Thus, adequate periods of abstinence must first be achieved, and then the patient reexamined for residual symptoms compatible with a nonaddictive, non-substance-induced psychiatric disorder ( 402). 

FIGURE 10—6. Depressive and anxious symptoms are not only a hallmark of major depressive disorder but are frequently associated with other psychiatric disorders, including bipolar disorder, schizophrenia, and schizoaffective disorder with organic causes of depression, such as substance abuse with childhood mood disorders (child) with psychotic forms of depression and with mood and psychotic disorders resistant to treatment with drugs (treatment-resistant), among others. 

A 75-year-old white man, without a history of psychiatric disorders, took cortisone 50 mg/day for 6 weeks for pulmonary fibrosis and developed severe obsessive-compulsive behavior without affective or psychotic symptoms. He was given risperidone without any beneficial effect. The dose of cortisone was tapered over 18 days. An MRI scan showed no signs of organic brain disease and an electroencephalogram was normal. His symptoms improved 16 days after withdrawal and resolved completely after 24 days. Risperidone was withdrawn without recurrence. 

Dr. J. F. J. Cade, an Australian psychiatrist, first reported on the beneficial use of a lithium compound for a psychiatric disorder, namely, manic behavior in 1949. The early human trials were undertaken after initial experiments on rats, which became quite lethargic after treatment with lithium urate. Fairly large doses were required for treating manic behavior and its use for this disorder has been displaced by organic drugs that carry less risk. His report, however, led to its current nse as a treatment for bipolar affective disorder (also known as manic-depressive disorder). Its use in the United States was curtailed for a decade and a half by the US. Food and Dmg Administration (FDA), which based its decision on incidental poisonings due to overuse of a lithium-based table salt substitute, despite a safe record of controlled psychiatric apphcations in Europe. It has been estimated that by 1985... 

Older classifications of psychiatric disorder divided diseases into psychoses and neuroses. The term psychosis is still widely used to describe a severe mental illness with the presence of hallucinations, delusions or extreme abnormalities of behaviour including marked overactivity, retardation and catatonia, usually accompanied by a lack of insight. Psychotic disorders therefore include schizophrenia, severe forms of depression and mania. Psychosis may also be due to illicit substances or organic conditions. Clinical features of schizophrenia may be subdivided into positive symptoms, which include hallucinations, delusions and thought disorder and negative symptoms such as apathy, flattening of affect and poverty of speech. 

Blockers such as propranolol, pindolol, and nadolol have been reported to have an antiaggression effect when used in a variety of psychiatric disorders, but particularly in the organic aggressive syndrome. Doses are typically higher than those required for cardiovascular /8-blockade, but patients should be monitored carefully for /8-blocker-related side effects. Patients may need to be treated with adequate doses for 6 to 8 weeks in order to evaluate an antiaggression response. 

Special emphasis should be placed on differential diagnosis among related disorders and between organic disorders and psychiatric disorders. 

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