Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.70.1A: Panniculitis, septal mostly + 10.70.1B: Fibrosing granulation tissue, abundant mucin, and scattered lymphocytes = Nodular fasciitis  The changes pictured are a response to external trauma akin to those in an early stage o…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…11.18.1B: Large amount of mucin in company with scattered spindle- and stellate-shaped fibrocytes, as well as mast cells = Scleromyxedema, early  This is an early lesion because mucin is so abundant in the reticular dermis. A synonym for the con…

Differential Diagnosis in Dermatopathology

Pretibial myxedema vs. Scleromyxedema

A systemic disease, which manifests itself in the skin first as violaceous macules and patches that tend to progress to papules and plaques, and sometimes to nodules and tumors, all of which represent hyperplasia of endothelial cells….

Histologic Diagnosis of Inflammatory Skin Diseases

Nodular fasciitis

…ial diagnosis histopathologic Fibrosarcoma exhibits abnormal spindle cells arranged in fascicles that tend to assume a herringbone pattern and does not display either abundant mucin or, as a finding consistent, an infiltrate of inflammatory cells….

Differential Diagnosis in Dermatopathology

Papular mucinosis vs Interstitial granuloma annulare

A systemic disease, which manifests itself in the skin first as violaceous macules and patches that tend to progress to papules and plaques, and sometimes to nodules and tumors, all of which represent hyperplasia of endothelial cells….

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Fibromatoses?

…ange from those composed largely of dense collagen with sparse spindle cells to densely cellular tumor-appearing masses. Classification: Palmar, plantar and penile fibromatosis Desmoid (Aggressive fibromatosis)” Cotran RS, Kumar V, Robbins SL….

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.92.1A: Fibrosing dermatitis and panniculitis, septal + 10.92.1B: Numerous multinucleate fibrocytes with large, hyperchromatic, pleomorphic nuclei = Radiation dermatitis, chronic  Abnormal fibrocytes, some of them multinucleate,…

Differential Diagnosis in Dermatopathology

Morphea, late stage vs. Collagenous nevus

A systemic disease, which manifests itself in the skin first as violaceous macules and patches that tend to progress to papules and plaques, and sometimes to nodules and tumors, all of which represent hyperplasia of endothelial cells….

Differential Diagnosis in Dermatopathology

Differential Diagnosis

…tion of collagen bundles by acid mucopolysaccharides 5. Mast cells increased markedly in regions mucinous 5. Mast cells increased slightly in loci mucinous 6. Fibrocytes increased slightly and scattered as solitary units in stroma, mucin-rich, mo…

Histologic Diagnosis of Inflammatory Skin Diseases

Scar

…lump fibrocytes that act in a manner comparable to mesenchymal cells of a follicular papilla in an embryo, those cells bring forth the entire infundibulo-apocrine-sebaceous-follicular unit. Low-grade fibrosarcoma consists of abnormal spindle cells ar…