While not often volunteered as a complaint, upon questioning, it has been found that pain is a common co-morbidity. Pains may include joint pain, muscle aches, headaches and stomachaches. Clinical experience has shown that after the OC and other psychiatric symptoms have improved, some children report pain for the first time. When widespread pain is present, patients often report other forms of sensory amplification and poor sleep. Physical exam may reveal areas of tenderness to palpation in the classic distribution for fibromyalgia. Patients who report both pain and stiffness upon awakening or after prolonged stationary positions should be assessed for arthritis. A small fraction of patients with PANS have been afflicted by an arthritis condition (inflammatory back pain, reactive arthritis, psoriatic arthritis, and juvenile idiopathic arthritis). Reactive arthritis (most commonly in the ankles, knees, and hips) has been reported before PANS onset. Involvement of the pediatrician, pediatric rheumatologist, pain specialist, occupational therapist, and physical therapist may help the course of the illness, alleviate pain and likely, improve emotional functioning.

The initial onset and subsequent exacerbations are usually incited by a variety of recognizable infections. Alternatively, these conditions may be associated with life stresses. In other cases, there is no clear inciting factor.

Brief psychotic disorder is a period of psychosis whose duration is generally shorter, is not always non-recurring, but can be, and is not caused by another condition.

The disorder is characterized by a sudden onset of psychotic symptoms, which may include delusions, hallucinations, disorganized speech or behavior, or catatonic behavior. The symptoms must not be caused by schizophrenia, schizoaffective disorder, delusional disorder or mania in bipolar disorder. They must also not be caused by a drug (such as amphetamines) or medical condition (such as a brain tumor). The term bouffée délirante describes an acute nonaffective and nonschizophrenic psychotic disorder, which is largely similar to DSM-III-R and DSM-IV brief psychotic and schizophreniform disorders.

Symptoms generally last at least a day, but not more than a month, and there is an eventual return to full baseline functioning. It may occur in response to a significant stressor in one's life, or in other situations where a stressor is not apparent, including in the weeks following birth. In diagnosis, a careful distinction is considered for culturally appropriate behaviors, such as religious beliefs and activities. It is believed to be connected to or synonymous with a variety of culture-specific phenomena such as latah, koro, and amok.

There are three forms of brief psychotic disorder:

1. Brief psychotic disorder with a stressor, such as a trauma or death in the family.

2. Brief psychotic disorder without a stressor, there is no obvious stressor.

3. Brief psychotic disorder with postpartum onset. Usually occurs about four weeks after giving birth.

The symptoms of chromium deficiency caused by long-term total parenteral nutrition are severely impaired glucose tolerance, weight loss, and confusion. However, subsequent studies questioned the validity of these findings.

Chromium deficiency is a proposed disorder that results from an insufficient dietary intake of chromium. Chromium was first proposed as an essential element for normal glucose metabolism in 1959, and was widely accepted as being such by the 1990s. Cases of deficiency have been claimed in hospital patients who were fed defined liquid diets intravenously for long periods of time.

By the turn of the century, these views were being challenged, with subsequent work suggesting that chromium supplements may present a health risk. In spite of this, dietary supplements containing chromium remain widely available.

Strangling is compression of the neck that may lead to unconsciousness or death by causing an increasingly hypoxic state in the brain. Fatal strangling typically occurs in cases of violence, accidents, and is one of two main ways that hanging may cause death (alongside breaking the victim's neck).

Strangling does not have to be fatal; limited or interrupted strangling is practised in erotic asphyxia, in the choking game, and is an important technique in many combat sports and self-defence systems.

Strangling can be divided into three general types according to the mechanism used:

- Hanging—Suspension from a cord wound around the neck

- Ligature strangulation—Strangulation without suspension using some form of cord-like object called a garrote

- Manual strangulation—Strangulation using the fingers or other extremity

Strangling involves one or several mechanisms that interfere with the normal flow of oxygen into the brain:

- Compression of the carotid arteries or jugular veins—causing cerebral ischemia.

- Compression of the laryngopharynx, larynx, or trachea—causing asphyxia.

- Stimulation of the carotid sinus reflex—causing bradycardia, hypotension, or both.

Depending on the particular method of strangulation, one or several of these typically occur in combination; vascular obstruction is usually the main mechanism. Complete obstruction of blood flow to the brain is associated with irreversible neurological damage and death, but during strangulation there is still unimpeded blood flow in the vertebral arteries. Estimates have been made that significant occlusion of the carotid arteries and jugular veins occurs with a pressure of around , while the trachea demands six times more at approximately .

As in all cases of strangulation, the rapidity of death can be affected by the susceptibility to carotid sinus stimulation. Carotid sinus reflex death is sometimes considered a mechanism of death in cases of strangulation, but it remains highly disputed. The reported time from application to unconsciousness varies from 7–14 seconds if effectively applied to one minute in other cases, with death occurring minutes after unconsciousness.

Early symptoms are malaise and lethargy. Even earlier might be a pain in a section of the gums which interferes with digestion. After 1–3 months, patients develop shortness of breath and bone pain. Myalgias may occur because of reduced carnitine production. Other symptoms include skin changes with roughness, easy bruising and petechiae, gum disease, loosening of teeth, poor wound healing, and emotional changes (which may appear before any physical changes). Dry mouth and dry eyes similar to Sjögren's syndrome may occur. In the late stages, jaundice, generalized edema, oliguria, neuropathy, fever, convulsions, and eventual death are frequently seen.

Scurvy is a disease resulting from a lack of vitamin C. Early symptoms include weakness, feeling tired, and sore arms and legs. Without treatment, decreased red blood cells, gum disease, changes to hair, and bleeding from the skin may occur. As scurvy worsens there can be poor wound healing, personality changes, and finally death from infection or bleeding.

Typically, scurvy is caused by a lack of vitamin C in the diet. It takes at least a month of little to no vitamin C before symptoms occur. In modern times, it occurs most commonly in people with mental disorders, unusual eating habits, alcoholism, and old people who live alone. Other risk factors include intestinal malabsorption and dialysis. Humans and certain other animals require vitamin C in their diets to make the building blocks for collagen. Diagnosis typically is based on physical signs, X-rays, and improvement after treatment.

Treatment is with vitamin C supplements taken by mouth. Improvement often begins in a few days with complete recovery in a few weeks. Sources of vitamin C in the diet include citrus fruit and a number of vegetables such as tomatoes and potatoes. Cooking often decreases vitamin C in foods.

Scurvy currently is rare. It occurs more often in the developing world in association with malnutrition. Rates among refugees are reported at 5% to 45%. Scurvy was described as early as the time of ancient Egypt. It was a limiting factor in long distance sea travel, often killing large numbers of people. A Scottish surgeon in the Royal Navy, James Lind, was the first to prove it could be treated with citrus fruit in a 1753 publication. His experiments represented the first controlled trial. It took another 40 years before the British Navy began giving out lemon juice routinely.

Mold (American English) or mould (British English) is part of the natural environment. Outdoors, molds play a part in nature by breaking down dead organic matter such as fallen leaves and dead trees; indoors, mold growth should be avoided. Molds reproduce by means of tiny spores. The spores are invisible to the naked eye and float through the air. Mold may begin growing indoors when spores land on moist surfaces. There are many types of mold, but all require moisture for growth.

Infants may develop respiratory symptoms as a result of exposure to "Penicillium", a fungal genus. Signs of mold-related respiratory problems in an infant include a persistent cough or wheeze. Increased exposure increases the probability of developing respiratory symptoms during the first year of life. Studies have indicated a correlation between the probability of developing asthma and exposure to "Penicillium".

Mold exposure has a variety of health effects, and sensitivity to mold varies. Exposure to mold may cause throat irritation, nasal stuffiness, eye irritation, cough and wheezing and skin irritation in some cases. Exposure to mold may heighten sensitivity, depending on the time and nature of exposure. People with chronic lung diseases are at higher risk for mold allergies, and will experience more severe reactions when exposed to mold. Damp indoor environments correlate with upper-respiratory-tract symptoms, such as coughing and wheezing in people with asthma.