Secondary obsessive-compulsive or related syndrome

Essential (Required) Features:

• The presence of prominent symptoms that are characteristic of Obsessive-Compulsive or Related Disorders, such as obsessions, compulsions, skin picking, hair pulling, or other body-focused repetitive behaviours.
• The symptoms are judged to be the direct pathophysiological consequence of a medical condition, based on evidence from history, physical examination, or laboratory findings. This judgment depends on establishing that:
• The medical condition is known to be capable of producing the symptoms;
• The course of the symptoms (e.g., onset, remission, response to treatment of the etiological medical condition) is consistent with causation by the medical condition; and
• The symptoms are not better accounted for by another mental disorder (e.g., an Obsessive-Compulsive or Related Disorder) or the effects of a medication or substance, including withdrawal effects.
• The symptoms do not meet the diagnostic requirements for Secondary Tics, classified in the grouping of Movement Disorders in the chapter on Diseases of the Nervous System.
• The symptoms are sufficiently severe to be a specific focus of clinical attention.

Boundary with other disorders and normality:

• Boundary with Obsessive-Compulsive or Related Disorders: Determining whether obsessive-compulsive or related symptoms are due to a medical condition as opposed to manifestations of a primary mental disorder is often difficult because the clinical presentations may be similar. Establishing the presence of a potentially explanatory medical condition that can cause obsessive-compulsive or related symptoms and the temporal relationship between the medical condition and the primary obsessive-compulsive or related symptoms is critical in diagnosing Secondary Obsessive-Compulsive or Related Syndrome. Secondary Obsessive-Compulsive or Related Syndrome is often characterized by clinical features that would be atypical for Obsessive-Compulsive or Related Disorders such as late age of onset, sudden appearance of symptoms, or accompanying cognitive impairment or focal neurological signs.
• Boundary with obsessive-compulsive or related symptoms caused by substances or medications, including withdrawal effects: When establishing a diagnosis of Secondary Obsessive-Compulsive or Related Syndrome, it is important to rule out the possibility that a medication or substance is causing the obsessive-compulsive or related symptoms. This involves first considering whether any of the medications being used to treat the medical condition are known to cause obsessive-compulsive or related symptoms at the dose and duration at which it has been administered. Second, a temporal relationship between the medication use and the onset of the obsessive-compulsive or related symptoms should be established (i.e., the obsessive-compulsive or related symptoms began after administration of the medication and/or remitted once the medication was discontinued). The same reasoning applies to individuals with a medical condition and obsessive-compulsive or related symptoms who are also using a psychoactive substance known to cause obsessive-compulsive or related symptoms either in the context of intoxication or withdrawal (e.g., cocaine-induced hair pulling, obsessions or compulsions due to amphetamine intoxication). In such cases, a diagnosis of a Substance-Induced Obsessive-Compulsive or Related Disorder should be assigned.

Potentially Explanatory Medical Conditions (examples):

Brain disorders and general medical conditions that have been shown to be capable of producing obsessive-compulsive or related syndromes include:

• Diseases of the Nervous System (e.g., epilepsy, Huntington disease, myoclonic disorders, Parkinson disease, paediatric autoimmune neuropsychiatric disorders associated with streptococcal infections [PANDAS], secondary chorea including chorea due to neuroacanthocytosis and McLeod syndrome, stroke)
• Certain Infectious or Parasitic Diseases (e.g., rheumatic chorea [Sydenham chorea])
• Endocrine, Nutritional or Metabolic Diseases (e.g., iron overload diseases such as pantothenate-kinase-associated neurodegeneration)
• Injury, Poisoning or Certain Other Consequences of External Causes (e.g., brain injury)
• Neoplasms (e.g., neoplasms of brain or meninges)