Excluding medical illnesses associated with psychosis is performed by using blood tests to measure:

Thyroid-stimulating hormone to exclude hypo- or hyperthyroidism,
Basic electrolytes and serum calcium to rule out a metabolic disturbance,
Full blood count including ESR to rule out a systemic infection or chronic disease, and
Serology to exclude syphilis or HIV infection.Other investigations include:

EEG to exclude epilepsy, and an
MRI or CT scan of the head to exclude brain lesions.Because psychosis may be precipitated or exacerbated by common classes of medications, medication-induced psychosis should be ruled out, particularly for first-episode psychosis. Both substance- and medication-induced psychosis can be excluded to a high level of certainty, using toxicology screening. Because some dietary supplements may also induce psychosis or mania, but cannot be ruled out with laboratory tests, a psychotic individuals family, partner, or friends should be asked whether the patient is currently taking any dietary supplements.Common mistakes made when diagnosing people who are psychotic include:
Not properly excluding delirium,
Not appreciating medical abnormalities (e.g., vital signs),
Not obtaining a medical history and family history,
Indiscriminate screening without an organizing framework,
Missing a toxic psychosis by not screening for substances and medications,
Not asking their family or others about dietary supplements,
Premature diagnostic closure, and
Not revisiting or questioning the initial diagnostic impression of primary psychiatric disorder.Only after relevant and known causes of psychosis are excluded, a mental health clinician may make a psychiatric differential diagnosis using a persons family history, incorporating information from the person with psychosis, and information from family, friends, or significant others. Types of psychosis in psychiatric disorders may be established by formal rating scales.
Linear gingival erythema (LGE) is a periodontal disorder diagnosed based on distinct clinical characteristics. It was originally thought that LGE was directly associated with HIV, and it was thus called HIV-associated gingivitis (HIV-G). Later research confirmed that LGE also occurs in HIV negative immunocompromised patients, and it was thus renamed. Presentation
LGE is limited to the soft tissue of the periodontium, appearing as a red line 2–3 mm in width adjacent to the free gingival margin. Unlike conventional periodontal disease, though, LGE is not significantly associated with increased levels of dental plaque.The prevalence of LGE remains unclear and there is no known treatment. == References ==