The question of the differential diagnosis of disorders of the depressive spectrum is quite complex. Here, the positions of researchers have been repeatedly revised both in connection with the change in ideas about depression, and in connection with the revision of the international classification of diseases.
Along with numerous statements about the specificity of the nosological symptoms of depression, there are data that clarify these ideas. Thus, examining the sensitivity of depression symptoms to electroconvulsive therapy, showed that a number of manifestations of this pathology demonstrate a correlation with insufficient therapeutic effect, and this fact was noted in both endogenous and reactive depression.
It should be noted that the criteria for the differential diagnosis of various disorders of the depressive spectrum are not sufficiently developed, and in this regard, special clinical, psychopathological, clinical, psychological and clinical-biological studies are required.
Despite the relativity of the notions “endogenous” and “psychogenic”, from the point of view of prognosis and treatment tactics, it has always been significant to separate endogenous and psychogenic depression. However, the complexity of this separation was also known, which led to the isolation of such intermediate forms as “endoreactive dysthymia”.
It is most difficult to differentiate depression within its recurrent options from depression in schizoaffective disorder or schizophrenia. The importance of accurate diagnosis in this case should be emphasized, since treatment tactics (for example, therapy with lithium or atypical antipsychotics) and the prognosis of the disease are determined here. Differential diagnosis in this case is based on the data of family history, clinical symptoms, the results of paraclinical studies, features of the course of the disease. Depression should be carefully assessed for its presence in other diseases: alcoholic psychosis, withdrawal syndromes, neurological diseases of the brain, etc. The diagnosis of schizoaffective disorder should not be made until the above pathology is ruled out.
Affective disorder is characterized by certain premorbid features (susceptibility to dysthymia, cyclothymia, anxiety); relatively acute onset of the disease; affective experience-causing affective disorders; despite the slowness of thinking, its consistency and consistency; mood-appropriate manifestations of psychosis (delusions and hallucinations); keeping personal identity; remitting nature of the disease; specific sleep disorders. In the family history may be indications of alcoholism or mood disorders. With a history of schizophrenia, one can identify schizoid or schizotypical personality traits, a gradual onset of the disease and its course without remission, rigid or flattened affect, special disturbances of thinking (disruption of the associative process), social disadaptation.
Most often, depression should be differentiated from mood disorders on the background of somatic illness. The coincidence of somatic and mental disorders in time, the severity of somatic pathology, its specificity, the disappearance of signs of depression as the treatment of somatic disease, are the most important criteria for differential diagnosis.
Depression should be distinguished from mood disorders caused by drug or alcohol use. In addition, it is necessary to differentiate depression from attention deficit disorder with increased activity. The latter is often complicated by secondary depression and may include some of its symptoms, especially low concentration, anxiety and insomnia. Disorders of adaptation reactions and their short duration speak against the presence of depression. Significantly distinguish depression from grief or loss. A sad mood is usually shorter than depression.