Mayo Test Catalog, (Sorted By Test Name) - Mayo Medical ...

FFTRO
57159
TWRP
80909
345 Oyster Point Boulevard
South San Francisco, CA 94080
Trofile DNA Co-Receptor Tropism Assay
Useful For: Trofile DNA uses cell associated viral DNA taken from whole blood cells infected with
HIV. HIV-1 envelopes encoded by the viral DNA are tested in a cell-based viral infectivity assay in order
to determine which co-receptor the HIV-1 virus population is capable of using: CCR5; CXCR4; or both,
known as D/M (dual/mixed).
Reference Values:
Trofile DNA Viral Classification
CCR5 Tropic (R5) HIV-1:
Virus uses CCR5 to enter CD4+ cells.
CXCR4 Tropic (X4) HIV-1:
Virus uses CXCR4 to enter CD4+ cells.
DUAL /MIXED Tropic (D/M) HIV-1:
Dual-tropic viruses can use either CCR5 or CXCR4 to enter
CD4+ cells. Mixed-tropic populations contain viruses with 2
or more tropisms.
Nonreportable:
Co-receptor tropism could not be determined. Common causes of
nonreportable results are reduced viral fitness or compromised
sample handling. Please note that Trofile DNA sample collection
and handling instructions differ from Trofile and other Monogram assays.
Test Performed By: Monogram Biosciences, Inc.
345 Oyster Point Boulevard
South San Francisco, CA 94080
Tropheryma whipplei, Molecular Detection, PCR
Clinical Information: Whipple disease is a chronic, systemic illness that in the majority of cases
involves the small intestine and its lymphatic drainage. The disease primarily affects middle-aged
individuals, with a peak incidence in the third and fourth decades. Clinical findings may include
malabsorption, chronic diarrhea, abdominal pain, arthralgia, fever, and central nervous system symptoms.
Pathologic changes associated with Whipple disease are distinctive, with diagnosis dependent on
histologic examination of biopsy specimens from involved tissues. Electron microscopic or special
high-resolution light microscopic examination of the lamina propria of the small intestine of patients with
untreated Whipple disease reveals many rod-shaped bacillary organisms. These tiny bacilli, referred to as
Whipple bacilli, measure about 0.25 micrometer long and are seen as periodic acid-Schiff-positive
granules within macrophages. These inclusions represent fragments of the cell walls from degenerating
bacilli. Culture of Whipple bacilli from biopsy material is laborious and the organism is very slow
growing. Definitive identification of the Whipple associated bacillus has been difficult because of these
limitations. Recently, molecular techniques using PCR and nucleotide sequencing allowed classification
of this bacillus as an actinomycete not closely related to any other known species, which has been named
Tropheryma whipplei.
Useful For: As an aid in diagnosis of Whipple disease, especially for identifying inconclusive or
suspicious cases
Interpretation: A positive result strongly suggests a diagnosis of Whipple disease. A negative result
Current as of January 3, 2013 2:22 pm CST 800-533-1710 or 507-266-5700 or MayoMedicalLaboratories.com Page 1804