Plasma Cell and other Disorders

Question 1

Multiple Myeloma

Answer 1

Malignant proliferation of Plasma Cells in Bone Marrow. Most common primary malignancy in Bone. High serum IL-6 sometimes. Cells activate RANK on osteoclasts - ‘punched-out’ lesions on x-ray of vertebrae and skull. Risk of fracture.
Ig leads to high plasma protein (M-spike).
Lack of antibody diversity- infection & death
Rouleaux formation.
Primary AL Amyloidosis - light chain.
Proteinuria (LightChain) Bence-Jones proteins
Deposition in Kidney Tubules: Renal Failure (Myeloma Kidney)

Question 2

Rouleaux formation

Answer 2

Increased serum protein (Multiple Myeloma’s Ig) decreases charge between RBCs and allows them to clump.

Question 3

Monoclonal Gammopathy of Undetermined Significance (MGUS)

Answer 3

Increased Serum protein (M-spike)

No lytic lesions, hypercalcemia, AL amyloid, or Bence-Jones Proteinuria.

Question 4

Waldenstrom Macroglobulinemia

Answer 4

B-cell Lymphoma of Monoclonal IgM
Generalized LAD
Increased protein with M-spike (IgM)
Visual and Neuro deficits (retinal hemorrhage or stroke)
Bleeding (platelet aggregation)
Tx with Plasmapheresis

Question 5

Langerhans Cell Histiocytosis

Answer 5

Neoplastic Prolif of Langerhans Cells
Birbeck (tennis racket) granules on EM
CD1a and S100 by immunohistochemi.

Question 6

Letterer-Siwe Disease

Answer 6

Malignant prolif of Langerhans cells
Skin Rash, Cystic Skeletal defect in infant
Multiple Organ systems
Rapidly fatal

Question 7

Eosinophilic Granuloma

Answer 7

Benign prolif of Langerhans cells in Bone
Presents as pathologic fracture in adolescent
Skin NOT involved
Langerhans mixed with inflammatory cells (including eosinophils) on biopsy.

Question 8

Hand-Schuller-Christian Disease

Answer 8

Malignant proliferation of Langerhans

Scalp rash, Lytic skull defects, Diabetes insipidus, exopthalmos in CHILD.