Chapter 5 - Ditzels Flashcards
Describe the appearance of and approach to cholesteatoma.
A keratinizing cyst filled with debris, and sometimes cholesterol clefts, inflammation & foreign body giant cells.
Consider inflammatory polyp, paraganglioma, middle ear adenoma, meningioma, and schwannoma.
Describe the appearance of and approach to sinus contents
Fragments of bone, respiratory and squamous mucosa, and mucous glands.
Consider chronic sinusitis, allergic fungal sinusitis (eosinophilic with charcot-leyden crystals, consider PAS/GMS)
Describe the appearance of and approach to plaques
An inner layer of elastic arterial wall, plus plaque, debris, thrombus… no real differential of concern.
Describe the appearance of and approach to IV discs.
Fibrocartilage and pulpy myxoid gel (nucleus pulposis), possibly with bone fragments. No differential.
Describe the appearance of and approach to thymus.
Lobular with dark outer cortex and pale medulla. Hassall’s corpuscles look like squamous nests. No germinal centers.
Weigh. Consider thymoma (sheets of cells or obliterated architecture).
Describe the appearance of and approach to heart valves.
Myxoid degeneration, calcification, and adherent vegetations.
Get bug stains if there are vegetations.
Describe the appearance of and approach to gallbladder.
Columnar epithelium in folds over a fibromuscular layer with Rokitansky-Aschoff sinuses.
Look for cholecystitis (chronic or acute!), cholesterolosis (foamy macrophages).
Describe the appearance of and approach to appendix.
Colonic mucosa with abundant lymphoid aggregates.
Look for neutrophils involving the wall (transmural) or serosa (serositis). If the serosa is inflammed but the wall isn’t, look elsewhere in the abdomen. Also look for carcinoid and wall mucin (as in mucinous cystadenoma/carcinoma).
Describe the appearance of and approach to hernia sac.
Fibroadipose tissue lined with mesothelium, often reactive or proliferative.
Watch out for incarcerated bowel, vas deferens, and metastatic tumor.
Describe the appearance of and approach to scar revisions.
Dense pink collagen, no appendages and thin epithelium. Hemorrhage, foamy macrophages, granulation tissue, suture & foreign body giant cells.
Exclude tumor and abscess.
Describe the appearance of and approach to knee bones / femoral heads
Thick cartilage layer with smooth surface and marrow between trabeculae.
Look for osteoarthritis (sclerotic bone with cysts, granulation tissue in marrow), osteonecrosis, osteopenia, and metastatic tumor.
Describe the appearance of and approach to limb amputations
Look for gangrenous necrosis, ulceration, scar, granulation tissue, and inflammation. Look for a “cause”, like atherosclerotic disease. Rule out fungal disease!
Describe the appearance of and approach to lipomas.
Mature fat cells with some fibrous tissue.
Exclude liposarcoma.
What are the 8 benign variants of lipoma?
Fibrolipoma
Myxolipoma
Chondroid lipoma
Myolipoma
Myelolipoma
Spindle cell lipoma
Pleomorphic lipoma
Angiolipoma
What are the features of liposarcoma?
Large deep-seated mass in the thigh, shoulder, retroperitoneum, or mesentery of an adult.
Chicken-wire vasculature, atypical cells, and lipoblasts.
Cholesteatoma
Arrow: Thin epithelium surrounding the keratin debris
Allergic mucin in rhinitis
Arrow: Tiger-stripe layers of eosinophils, mucin, and cell debris.
Inset: Black fungal hyphae on GMS
Carotid plaque
Arrow: Cholesterol clefts.
Arrowhead: Foamy macrophages
Intervertebral disc
Thymus
Arrow: Hassall’s corpuscles
Parathyroid tissue.
Arrow: Oxyphil cells
Arrowhead: Chief cells
Heart valve
Arrow: Myxoid degeneration
Gallbladder with cholesterolosis.
Arrow: Foamy macrophages distending mucosal folds
Arrowhead: Rokitansky-Aschoff sinuses
Appendicitis.
Arrow: Residual colonic mucosa
Arrowhead: Fibrinopurulent debris
Hernia sac.
Arrow: Delicate mesothelial lining
Dermal scar.
Note pale and homogeneous collagen without adnexal structures.
Osteoarthritis
- Eroded cartilage with abnormal mineralization
- Subchondral trabecular thickening
- Myxoid degeneration and subchondral cysts
- Residual hematopoietic marrow
Osteonecrosis
Arrow: Necrotic bone marrow
Arrowhead: Dead osteocytes
Gangrenous necrosis.
Arrow: Residual epidermis
Arrowhead: Debris, dying cells & bacteria
Lipoblast in atypical lipoma
Arrow: Fat vacuoles indenting the nucleus
Arrowhead: Hyperchromatic cells within the fibrous stroma
