Papulosquamous disorders

Papulosquamous disorders 

Updated: 02/10/2021

© Jun Wang, MD, PhD

General features
  • Papulo-: Papules and plaques
  • Squamous: Scaly
  • Common skin diseases with dermal inflammation and epidermal hyperkeratosis or desquamation
  • Histological features may be seen in other conditions such as infections, premalignant and malignant dermatoses
  • Drug eruption and dermatophytosis may cause same clinical presentations
Koebner phenomenon
  • New skin lesion on areas of cutaneous injury, also known as isomorphic response
  • May be associated with psoriasis and lichen planus
  • Same clinical and histological features as original lesions
  • NOT due to the seeding of an infectious agent, an allergic reaction to a contact agent, or skin breakdown
  • May form with or without pre-existing skin conditions
  • Confirmed by experimentally reproducing lesions with injury
  • “All or nothing” response:
Patients who develop Koebner phenomenon in response to one method of injury are susceptible to other stimuli
A patient who does not develop skin lesions with one type of injury is NOT expected to exhibit Koebner phenomenon with another type of injury
Entities to be discussed

Practice questions


Back to contents

Comments

Post a Comment

Popular posts from this blog

Contents

Pathology notes Jun Wang, MD, PhD 1. General information Frequently discussed syndromes Terms of dermatology Terms of hematology 2. Primary immunodeficiency disorders 3. Hemodynamic abnormalities Shock Thrombosis and embolism Bleeding disorders 4.  Benign blood cell disorders Anemia Benign white cell disorders 5. Hematopoietic neoplasms Lymphoid neoplasms Myeloid neoplasms Histiocytic neoplasms: Langerhans cell histiocytosis 6. Cardiovascular system Pulmonary hypertension Cardiovascular system tumors 7. Respiratory tract tumors 8. Gastrointestinal tract Congenital disorders Infectious gastroenteritis Oral cavity Esophagus Stomach Intestinal tumors Salivary glands Exocrine pancreas and gallbladder 9. Urinary system Kidney masses Lower urinary tract 10. Male reproductive system 11. Female genital tract 12. Breast 13. Endocrine organs Pituitary gland Adrenal gland Thyroid gland Parathyroid gland Endocrine pancreas M
Read more

Anemia

Anemia Updated: 07/13/2024 © Jun Wang, MD, PhD   General features Decrease in red cell mass Hemoglobin: Levels of hemoglobin in a specific volume of whole blood Hematocrit: Fraction of whole blood composed of red blood cells Red cell count: Quantity of red cell in a specific volume of whole blood Three major groups based on RBC sizes Microcytic Normocytic Macrocytic Three major causes Blood loss: acute or chronic Increased red cell destruction: hemolysis Reduced production: marrow failure due to genetic abnormality or nutritional deficiency Etiology Genetic abnormality Hemoglobinopathies RBC cytoskeletal abomorlities Enzyme abnormalities Fanconi anemia Nutritional deficiencies: iron, VB12, folate, general malnutrition Physical etiologies: trauma, burns, frostbite, prosthetic valves, etc Chronic diseases: chronic infections, neoplasia, autoimmune disorders, kidney or liver diseases, etc Infectious diseases: hepatitis, sepsis , malaria, etc
Read more

Lymphoid neoplasms

Lymphocytic neoplasms Updated: 05/17/2020 © Jun Wang, MD, PhD Terminology Lymphoma : Proliferations forming discrete tissue masses Leukemia : Widespread involvement of the bone marrow and usually the peripheral blood Any "lymphoma" can present with or evolve to a leukemic picture, and any "leukemia" can occasionally present with a mass lesion Other hematology terms Important risk factors Immunodeficiency (primary or secondary) Autoimmune disorders Viruses (HIV, KSHV/HHV8, HTLV-1) H. pylori infection Radiation Chemotherapy Diagnostic approaches Complete history, especially those with possible epidemic characters, such as Burkitt lymphoma CBC, Bone marrow Morphology/immunohistochemistry Immunofluorescence flow cytometry Cytogenetic studies Molecular studies Commonly used markers All lymphomas: CD45 B-cell neoplasms: CD5, CD10, CD19, CD20, CD79a, CD23, bcl2, bcl6, cyclin D1, light chai
Read more