Other viruses (ASCPi)

HIV-1

It is a more pathogenic strain than other HIV strains

Group M

HIV-1 group responsible for the majority of HIV-1 infections worldwide

B

Most predominant HIV-1 subtype in the U.S. and Europe

C

Most predominant HIV-1 subtype worldwide

HIV-2

Which HIV strain is predominant in West Africa?

Gp41/Gp120 complex

It is the primary envelope glycoprotein on the surface of HIV-1

p24

It is the nucleocapsid core protein of the HIV virus

p17

It is the matrix shell protein of HIV

Western blot assay

The most sensitive and specific test for HIV-1

• p24

• gp41

• gp120/160

CDC criteria for a positive western blot test includes the presence of at least 2 out of 3 of these possible bands:

• Use recombinant antigens instead of viral lysates

• Repeat test with the same or fresh specimen

• Testing with a new specimen obtained 4 to 6 weeks later

Resolutions for an indeterminate western blot result:

• Bloodborne

• Sexual contact

• Vertical (mother-to-fetus)

What are the modes of transmission of HTLV?

• ATL

• HAM/TSP

HTLV-I is the cause of two diseases:

ATL

Characterized by a monoclonal proliferation of mature T cells that express the surface markers, CD3, CD4, and CD25

Downey cells

The blood sample of a patient suspected with Epstein-Barr virus has been subjected to peripheral blood smearing. Which cells are indicative of EBV?

• Saliva

• Blood transfusion

• Transplacental

What are the modes of transmission of EBV?

Infectious mononucleosis (Kissing disease)

Acute infectious disease of the mononuclear phagocyte system

VCA

Antigen produced by infected B cells and can be found in the cytoplasm

EBNA

Antigen found in the nucleus of all EBV infected cells

4-7 days

Anti-VCA IgG is usually detectable within how many days after the onset of signs and symptoms?

1:56 or greater

Titer amount that is clinically significant in patients with suspected infectious mononucleosis

Paul-Bunnell Test

Heterophile antibody test in which sheep RBCs agglutinate in the presence of heterophile Abs

Monospot test

Rapid slide agglutination method which tests the ability of serum absorbed with guinea pig kidney or beef erythrocyte antigens to agglutinate horse red blood cells

Forssman

Type of heterophile antibody that is:

• Absorbed by Guinea pig kidney cells

• Not absorbed by Beef erythrocytes

IM

Type of heterophile antibody that is:

• Not absorbed by Guinea pig kidney cells

• Absorbed by Beef erythrocytes

Serum Sickness

Type of heterophile antibody that is both absorbed by Guinea pig kidney cells and beef erythrocytes

Cytomegalovirus

• It is the most common cause of congenital infections

• It is the most important infectious agent associated with organ transplantation

Immunocompromised patients

Amplification of CMV DNA by PCR is best for:

Virus isolation from neonatal urine or saliva within 3 weeks postpartum

A congenital CMV diagnosis is established by:

Togaviridae

Rubella virus belongs to the family:

• Respiratory droplets

• Transplacental infection

Rubella is transmitted through:

RT-PCR

The most widely used molecular method for Rubella

Serology tests

What type of tests are the most common means of confirming a Rubella diagnosis?

ELISA

It is the most commonly used serology test to confirm a Rubella diagnosis

• 1:16

• 1:64

• 1:512

Titer level/s found in acute and past infections of Rubella

Testing for IgM antibody

It proves to be invaluable for the diagnosis of congenital rubella syndrome in the neonate.

Congenital rubella syndrome

Demonstration of IgM in a single neonatal specimen is diagnostic of:

Rotavirus

The most common cause of viral gastroenteritis in infants and children

ELISA and Latex Agglutination

Which tests detect Rotavirus antigens in fecal material?

SLE

Chronic systemic inflammatory disease which has a strong association with HLA DR and DQ

Renal failure

It is the most frequent cause of death in patients with SLE

Diffuse proliferative glomerulonephritis (DPGN)

Most dangerous type of lesion in patients with SLE

• Malar rash

• Discoid rash

• Photosensitivity

• Oral ulcers

• Arthritis

• Serositis

• Renal disorders

• Neurological disorders

• Hematologic disorders

• Immunologic disorders

• Presence of antinuclear antibodies

In order for a clinical diagnosis of Lupus to be made, four of eleven specific criteria must be present:

Homogeneous

Immunofluorescent pattern of Anti-dsDNA and Anti-histone

Drug-induced SLE

Anti-histone is associated with:

Anti-Sm

Which antibody is the most diagnostic for SLE?

FANA

• Most widely used and accepted test for diagnosing SLE

• Mouse kidney or human epithelial HEp-2 cells are fixed to a slide and allowed to react with patient serum

1:80 (1:160 if patient is <65 yrs old)

In FANA testing, is is now a common practice to screen with _____ dilution to avoid low positive titers in the normal population

Double-stranded DNA (ds-DNA) antibodies

Which antibodies are the most specific for SLE?

Anti-SSA (RO)

Antibody often found in patients with cutaneous manifestations of SLE, can bind to neutrophil surface and cause neutropenia

Anti-SSB (La)

Antibody found in only 10 to 20 percent of patients with SLE

anti-nRNP

Anantibody directed against Ribonucleoprotein complexed with a nuclear RNA called U1-nRNP

Antiphospholipid antibodies

• Antibodies especially associated with deep-vein and arterial thrombosis and with morbidity in pregnancy

• Patients with this antibody have an increased risk of clotting and spontaneous abortion

Clotting and spontaneous abortion

Patients with antiphospholipid antibodies have an increased risk of:

Nuclear rim (peripheral)

Staining pattern which indicates the active stage of SLE

Homogenous (solid/diffuse)

Staining pattern seen in rheumatoid disorders and other connective tissue defect

Speckled

Which staining pattern involves extractable nuclear antigens (ENA) such as Smith (Sm) antigen and ribonucleoprotein (RNP)?

Nucleolar

Which staining pattern is present in progressive systemic sclerosis?

Thready

Which staining pattern may be seen in SLE but not in RA?

Discrete, Speckled

Crest variant of PSS