Practice question answers, vesiculobullous disorders

Practice question answers
Vesiculobullous disorders
Updated: 03/01/2019
© Jun Wang, MD, PhD

1. E. Suprabasal vesicles with acantholysis is most compatible with pemphigus. Bullous pemphigoid is characterized by large tense blisters involving flexor surfaces, trunk and mucosa, and microscopically it has subepidermal blisters without acantholysis. Dermatitis herpetiformis has clusters of small pruritic vesicles or pustules, and microscopically it has subepidermal vesicle with neutrophilic aggregates. Epidermolysis bullosa usually has a history of blistering disorder right after birth. Herpes infection has cytological changes of multinucleation, nuclear molding and chromatin margining.

2. A. Pemphigus is caused by autoimmune destruction of desmosomal components desmoglein 1 and/or 3. Congenital defects of cytoskeletal components are seen in epidermolysis bullosa. Trauma may be associated with epidermolysis bullosa. UV-light is currently the leading risk factor for skin cancers. Viral infection can be associated with various dermatosis, including herpes and erythema multiforme, but not pemphigus.

3. B. Immunofluoscence feature for pemphigus is IgG deposit at intercellular junctions of keratinocytes, where desmosomes are. Clumped IgM deposit at dermoepidermal junction is seen in lichen planus. Granular deposit of IgA at dermal papillae is seen in dermatitis herpetiformis. Linear deposit of IgG at dermoepidermal junction is seen in bullous pemphigoid.

4. C. Pemphigus is caused autoimmune destruction of desmosomal components desmoglein 1 and/or 3. Autoimmune injury of BP180 or BP230 is seen in bullous pemphigoid. Congenital defects of keratin 5/14, laminin 5 and collage VII are seen in epidermolysis bullosa, simplex type, junctional type and dystrophic type, respectively.

5. D. Pemphigus with vesicles at granular layer is foliaceus type, an endemic in Brazil and Columbia. Bullous pemphigoid is characterized by large tense blisters involving flexor surfaces, trunk and mucosa, and microscopically it has subepidermal blisters without acantholysis. Epidermolysis bullosa usually has a history of blistering disorder right after birth. Pemphigus erythematosus has SLE type malar rash on face. Pemphigus vegetans is characterized by acanthosis, suprabasal vesicles and intraepidermal microabscess.

6. D. See discussion of question 5.

7. A. See discussion of question 2.

8. A. See discussion of question 1.

9. A. See discussion of questions 2 and 4.

10. A. See discussion of question 4.

11. D. See discussion of question 3.

12. B. See discussion of question 1.

13. C. See discussion of question 3. Linear deposit of IgA along dermoepidermal junction is seen in linear IgA bullous dermatosis.

14. C. Dermatitis herpetiformis is associated with celiac disease (gluten hypersensitivity). Absence of enteric ganglion is seen in Hirschprung disease. Autoimmune gastritis and duodenitis is more common in older population. Herpes gastritis is extremely rare, and usually does not have skin manifestions. Pyloric smooth muscle hyperplasia is associated with hypertrophic pyloric stenosis.

15. C. Epidermolysis bullosa, simplex type, is characterized by basal layer vesicles formation and basal cell degeneration, while junctional type and dystrophic type usually have subepidermal vesicles. Also see discussion of question 1.

16. D. See discussion of question 4.

17. B. Immunofluoscence mapping is used to differentiate subtypes of epidermolysis bullosa. Gram stain and culture is useful for bacterial infection. Lymphocyte phenotyping is useful for lymphocytic neoplasms and immunodeficiency disorders. Quantitative serum immunoglobulin levels are tests for immunodeficiencies and B cell/plasma cell disorders. Viral DNA analysis is tested for viral infections.

18. B. Although all subtypes of epidermolysis bullosa have recurrent blistering, “mitten deformity” is consistent with dystrophic type. Bullous pemphigoid is characterized by large tense blisters involving flexor surfaces, trunk and mucosa, without mitten deformity, and tend to occur in older population. Kindler syndrome has other presentations besides acral skin blistering, including photosensitivity, progressive poikiloderma and diffuse cutaneous atrophy.

19. B. See discussion of question 4.




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