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Rhizopus nigricans (Allergen Specific IgE)

Rhizopus nigricans (m11)

Test Codes

Antrim #31965, EPIC: LAB5698, SOFT: ERHN

Department

Special Testing Allergens

Specimen Collection Criteria

Collect: One Gold-top SST tube.

Twenty individual allergen assays or allergen screens can be performed on one 5 mL Gold-top SST tube. Each allergen assay requires 100 mcL of serum.

Physician Office/Draw Specimen Preparation

Let specimen clot 30-60 minutes then immediately centrifuge to separate serum from cells. Refrigerate (2-8°C or 36-46°F) the centrifuged collection tube within two hours of collection.

Preparation for Courier Transport

Transport: Centrifuged collection tube, refrigerated (2-8°C or 36-46°F).

Rejection Criteria

Plasma specimens.

Severely lipemic or hemolyzed specimens.

In-Lab Processing

Let specimen clot 30-60 minutes then immediately centrifuge to separate serum from cells. Room temperature is acceptable for a maximum of two hours.

Storage

Specimen Stability for Testing:

Centrifuged SST Tubes and Microtainers^® with Separator Gel
Room Temperature (20-26°C or 68-78.8°F): 2 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): Unacceptable

Red-top Tubes and Microtainers^® without Separator Gel
Room Temperature (20-26°C or 68-78.8°F): 2 hours
Refrigerated (2-8°C or 36-46°F): Unacceptable
Frozen (-20°C/-4°F or below): Unacceptable

Serum Specimens (Pour-Overs)
Room Temperature (20-26°C or 68-78.8°F): 2 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): 1 month

Specimen Storage in Department Prior to Disposal:

Refrigerated (2-8°C or 36-46°F): 7 days

Laboratory

Royal Oak Special Testing Laboratory

Performed

Monday – Friday.
Results available the next business day.

Reference Range

Allergy Reference Range: Less than 0.35 kU/L. 

Range (kU/L)	Class	Interpretation
Less than or equal to 0.34	0	Negative
0.35-0.69	1	Low
0.70-3.49	2	Medium
3.50-17.49	3	High
17.50-49.99	4	Very High
50.0-100.0	5	Very High
Greater than 100	6	Very High

Test Methodology

Fluorescence Enzyme Immunoassay (FEIA).

Interpretation

The allergen class may not be predictive of clinical disease in some patients. The diagnosis of allergy should be based upon patient history and clinical findings. The diagnosis of allergy should not be based upon laboratory findings alone.

Clinical Utility

Positive assay results indicate a high probability of allergic disease. Negative assay results effectively rule out allergy induced by those allergens.

Clinical Disease

Mucor and Rhizopus are common inhabitants of soil and found in high concentrations in decaying leaf matter and organic breakdown materials. The spores are not commonly found free in the air (1). Rhizopus is also found in strawberries, sweet potatoes, and in nests, feathers and waste products of wild birds. The transmission mechanism of a fungus, such as Rhizopus, is through spore or mold particle inhalation. Upon inhalation of the spores or fragments of the mold, the allergic individual will commonly develop symptoms of coughing, shortness of breath, accumulation of mucus and rarely, hypersensitivity pneumonitis. Skin reactivity with Rhizopus shows similar variability as Mucor, however, a stronger pattern of reactivity is generally associated with Rhizopus species (1).

Cheeses and other foods prepared with fungi may produce an allergic response or intensify an allergic reaction in patients with fungal allergies. Less often, consumption of dried fruits, mushrooms, soy sauce or vinegar may initiate an allergic response in patients with fungal allergies.

Rhizopus is found year round indoors in warm, dry habitats (1).

Reference

1. Middleton, E., Charles Reed, Elliot Ellis, N. Franklin Adkinson, John Yunginger, and William Busse. Allergy Principles and Practice. Volume I. 4th ed. Mosby: St. Louis. 1993. Pp. 510, 538.

CPT Codes

86003
LOINC: 6229-9

Contacts

Last Updated

3/21/2023