Integumentary System Diagnostic Test Grid

Name of Test

Test Type

Normal Adult Findings

Indications for Test

Interfering Factors & Contraindications

Clinical Significance of Findings

Skin Biopsy

Herpes Simplex

Microscopic Study

No virus present

No HSV antibodies present

Used on patients with suspected initial genital infections

Or on immunocompromised patients with oral or genital eruptions or fever of unknown origin

N/A

To diagnose acute initial herpes infections

Culture is still the standard criteria for detection of HSV and can identify HSV in 90% of patients

These tests are used to supplement cultures

Culture and Sensitivity of Wound and Soft Tissue

Allergy Skin Testing

Antiscleroderma antibody

Blood test

Positive:

Scleroderma (PSS),

CREST syndrome: CREST is a variant of scleroderma. In both of these diseases the autoimmune response is targeted to the endothelium of blood vessels. Fibrosis occurs. This, combined with deposit of collagen-related tissue, creates the organ changes seen in the skin, GI tract, and other internal organs.

This antibody is diagnostic for scleroderma (progressive systemic sclerosis [PSS]) and is present in 45% of patients with that disease.

Drugs that may cause increased levels include amino salicylic acid, isoniazid, methyldopa, penicillin, propylthiouracil, streptomycin, and tetracycline.

In general, the higher the titer of Scl-70 antibody, the more likely it is that PSS exists and the more active the disease is. As the disease becomes less active because of therapy, the Scl-70 antibody titers can be expected to fall.

Varicella Zoster Virus

Fungal Infection Testing

Fungus can be cultured from blood, body fluids, CSF, fresh tissue, bronchopulmonary secretions, swabs of the ear, nose, and throat, or from urine.

Increased Levels

Acute fungal infection

Candidiasis, thrush, yeast of mouth/esophagus, Pulmonary infection, Infection of the lung, bloodstream; meningitis

False-positive results can occur if a patient’s intestinal tract is colonized with Candida.

False-positive results occur in patients on hemodialysis using cellulose membranes.

False-negative results occur in serum that is hemolyzed, icteric, lipemic, or turbid.

Increased Levels

Acute fungal infection,

Previous systemic exposure to fungal disease:

While prior fungal exposure will not provide positive cultures, antibodies to fungal infection may persist long after acute infection has been treated.

Antinuclear Antibody (ANA)

Blood Test

Negative at 1:40 dilution

To diagnose SLE and other autoimmune disorders

Certain drugs can cause false positives or false negatives

ANA is a group of protein antibodies that react against cellular material and is sensitive for diagnosing SLE.

Almost all patients with SLE develop autoantibodies, so a negative ANA test excluded SLE. If the ANA test is positive, other antibody tests must be done to confirm their diagnosis

Positive ANA levels can also be indicative of other autoimmune disorders