We have posted updates of the following topics:Skin nontumor > Dermal collagen and elastic tissue alterations, and cutaneous deposits > Ochronosis
by Chico J. Collie, M.B.B.S., Jonathan D. Ho, M.B.B.S., D.Sc.
Topic summary: Disorders characterized by deposition of homogentisic acid in connective tissue. Blue-gray to black pigmentation due to deposition of ochre colored pigment. Increased urinary levels of homogentisic acid on gas chromatography mass spectrometry analysis in alkaptonuria. Xray findings in alkaptonuric arthropathy include joint space narrowing, osteophyte formation, joint space calcification and reactive sclerosis of articular surfaces. Microscopic features of ochronosis are similar in both alkaptonuria and exogenous ochronosis.
Transfusion medicine > Immunotherapy > COVID-19 convalescent plasma Transfusion medicine > Immunotherapy > COVID-19 convalescent plasma
by Kyle Annen, D.O.
Topic summary: Convalescent plasma is obtained from a blood donor who has recently recovered from the relevant infection. COVID-19 convalescent plasma is an investigational blood product used to treat patients who are infected with the novel coronavirus. COVID-19 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an enveloped, positive stranded RNA virus that is adapted to infect many animals, including humans. Convalescent plasma has been shown to be most effective when given early (< 3 days) and with a high titer IgG dose (≥ 1:1,350).
Transfusion medicine > Red blood cell antigens > Kell group
by Brian D. Adkins, M.D., Garrett S. Booth, M.D., M.S.
Topic summary: Highly immunogenic; antibodies clinically significant. Most Kell antigens are widely expressed on the surface of red blood cells in the donor population. Antibodies occur with transfusion, pregnancy or activities such as intravenous drug use. Exposure to Kell antigens secondary to pregnancy or transfusion. McLeod syndrome is an X-linked disease characterized by neuromuscular symptoms, such as cognitive abnormalities, movement disorders and psychiatric symptomology and ongoing hemolytic anemia, caused by an absence of the Xk protein (which expresses the Kx antigen).
Transfusion medicine > Transfusion medicine regulatory > Tissue banking
by Louise Helander, M.B.B.S., Kyle Annen, D.O.
Topic summary: Retrieval, storage and distribution of human tissues for medical use. Includes bone, cardiac (e.g. valves) and vascular tissue, corneas and retinas, dura mater, reproductive tissue (including gestational tissue), skin and cellular tissues. Donor screening includes donor risk assessment interview (DRAI) conducted with donor or designee. All tissue is collected aseptically using standard surgical preparations. Tissue records (donor consent, eligibility, processing, storage, distribution) maintained for at least 10 years after date of tissue distribution, transplant, disposition or expiration (whichever is longest).
Vulva, vagina & female urethra > Mesenchymal neoplasms > Epithelioid sarcoma
by David B. Chapel, M.D., Jennifer A. Bennett, M.D.
Topic summary: Rare malignant neoplasm of the vulva and deep pelvic soft tissue characterized by SMARCB1 / INI1 deletion. In vulva and pelvic soft tissues, proximal type epithelioid sarcoma > distal type. It affects women, 17 – 80 years, most often in fourth and fifth decades. Vulvar epithelioid sarcoma most often involves the labia majora and mons pubis. Diagnosis typically established on examination of excision specimen. Treatment involves early wide en bloc excision or radical vulvectomy with node dissection; local excision is inadequate.