Paraphrenia is a mental disorder characterized by an organized system of paranoid delusions with or without hallucinations (the positive symptoms of schizophrenia) and without deterioration of intellect or personality (its negative symptom).This disorder is also distinguished from schizophrenia by a lower hereditary occurrence, less premorbid maladjustment, and a slower rate of progression. Onset of symptoms generally occurs later in life, near the age of 60. The prevalence of the disorder among the elderly is between 0.1% and 4%.Paraphrenia is not included in the DSM-5; psychiatrists often diagnose patients presenting with paraphrenia as having atypical psychosis, delusional disorder, psychosis not otherwise specified, schizoaffective disorders, and persistent persecutory states of older adults. Recently, mental health professionals have also been classifying paraphrenia as very late-onset schizophrenia-like psychosis.In the Russian psychiatric manuals, paraphrenia (or paraphrenic syndrome) is the last stage of development of paranoid schizophrenia. "Systematized paraphrenia" (with systematized delusions i. e. delusions with complex logical structure) and "expansive-paranoid paraphrenia" (with expansive/grandiose delusions and persecutory delusions) are the variants of paranoid schizophrenia (F20.0). Sometimes systematized paraphrenia can be seen with delusional disorder (F22.0). The word is from Ancient Greek: παρά – beside, near + φρήν – intellect, mind. Signs and symptoms
The main symptoms of paraphrenia are paranoid delusions and hallucinations. The delusions often involve the individual being the subject of persecution, although they can also be erotic, hypochondriacal, or grandiose in nature. The majority of hallucinations associated with paraphrenia are auditory, with 75% of patients reporting such an experience; however, visual, tactile, and olfactory hallucinations have also been reported.
A lack of insulin in the bloodstream allows unregulated fatty acid release from adipose tissue which increases fatty acid oxidation to acetyl CoA, some of which is diverted to ketogenesis. This raises ketone levels significantly above what is seen in normal physiology. Alcohol
Alcoholic ketoacidosis is caused by complex physiology that is usually the result of prolonged and heavy alcohol intake in the setting of poor nutrition. Chronic alcohol use can cause depleted hepatic glycogen stores and ethanol metabolism further impairs gluconeogenesis. This can reduce glucose availability and lead to hypoglycemia and increased reliance on fatty acid and ketone metabolism. An additional stressor such as vomiting or dehydration can cause an increase in counterregulatory hormones such as glucagon, cortisol and growth hormone which may further increase free fatty acid release and  ketone production. Ethanol metabolism can also increase blood lactic acid levels which may also contribute to a metabolic acidosis. Starvation
Starvation is a rare cause of ketoacidosis, usually instead causing physiologic ketosis without ketoacidosis. Ketoacidosis from starvation most commonly occurs in the setting of an additional metabolic stressor such as pregnancy, lactation, or acute illness. Medications
Certain medications can also cause elevated ketones, such as SGLT2 inhibitors causing euglycemic ketoacidosis. Overdose of salicylates or isoniazid can also cause ketoacidosis. Toxins
Ketoacidosis can be the result of ingestion of methanol, ethylene glycol, isopropyl alcohol, and acetone. Pathophysiology
Ketones are primarily produced from free fatty acids in the mitochondria of liver cells.