Innate Cells and Tissues

Question 1

Asplenia

Answer 1

This disorder can be either inherited or due to trauma. Macrophages in the spleen are important for recognizing and phagocytosing complement-labeled or antibody-opsonized bacteria from the bloodstream.

Patients are susceptible to capsular bacteria.

Patients should get vaccines for encapsulated bacteria and should take antibiotics prophylatically prior to dental work or if feel a respiratory issue coming on.

Question 2

NK Cell Deficiencies (3)

Answer 2

Absolute NK-cell deficiency: total lack of NK cells

Classical NK-cell deficiency: Fewer NK cells, and those that do exist have diminished function.

Functional NK cell deficiency: Normal number of NK cells, but they lack functionality.

Patients are susceptible to opportunistic species of mycobacterium, the fungus Tricophyton, varicella zoster, herpesvirus, ctyomegalovirus, and Epstein Barr.

Diagnosis: difficult

Question 3

NEMO

Answer 3

NEMO is a genetic defect in a protein required for NFkB activity, which is needed for transcription of genes following PRR engagement.

Phenotype: deep set eyes, fine hair, conical teeth, and blistering skin.

Patients suffer from recurrent bacterial and viral pathogens.

Question 4

Lymphocyte adhesion deficiency

Answer 4

Results from genetic deficiency of functional CD18. Without CD18, phagocyte migration into inflamed tissues is defective.

Patient is susceptible to extracellular pathogens and encapsulated bacteria.

Presentation: Delayed detachment and sloughing of the umbilical cord

Question 5

Chronic Granulomatous Disease

Answer 5

Results from defective NADPH oxidase that results in phagocytes that cannot produce toxic oxygen intermediates.

Patients are susceptible to chronic bacterial and fungal infections.

If infant presents with Serratia marcescens, test for CGD.

Two tests for CGD are nitroblue tetrazolium dye (blue means no disease) and dihydrorhodamine to rhodamine (fluoresce green means no disease)

Question 6

Chediak-Higashi Syndrome

Answer 6

Caused by a genetic defect of the gene that codes for LYST, which controls intracellular vesicle formation. Patients cannot fuse phagosomes with lysosomes to rid of pathogens. Neutrophil granules will be large and irregularly shaped.

Presentation: Partial albinism, recurrent pyogenic infections, and neurological disorders.

Question 7

Neutropenias

Answer 7

Kostmann Syndrome: caused by abnormality of granulocyte colony stimulating factor (G-CSF); patients susceptible to bacterial and fungal infections, including flora microbes.

Cyclic neutropenia: cause by a defect in the gene that codes for elastase. The condition occurs every 2-4 weeks and last for about a week.

Benign chronic: low, but not life-threatening, neutropenia. Often asymptomatic.