Joints and Soft Tissue Tumors MCQs

SERONEGATIVE ARTHRITIS REFERS TO A GROUP OF FOUR CHRONIC DISEASES - ANKYLOSING SPONDYLITIS, PSORIATIC ARTHRITIS, REACTIVE ARTHRITIS, AND ENTEROPATHIC ARTHRITIS. ALL OF THEM ARE NEGATIVE FOR RHEUMATOID FACTOR, THEY'RE ALL POSITIVE FOR HLA-B27, AND THEY TYPICALLY ALL RUN IN FAMILIES. Reference: Robbins, 10 th edition, page number- 822

Explanation: Rheumatoid arthritis (RA) is a chronic autoimmune condition in which the immune system attacks healthy joint tissues. In genetically susceptible individuals, exposure to specific antigens activates CD4+ T-cells. These T-cells release inflammatory cytokines, including TNF-α, IL-1, IL-6, and interferon-γ, which in turn activate endothelial cells, B-cells, and macrophages. This immune cascade leads to persistent inflammation, joint damage, and the characteristic deformities of RA. Explanation of other options: IgE-mediated (Option A): Primarily seen in allergic reactions, not in RA. Defective cellular and humoral immunity (Option B): RA involves targeted autoimmunity rather than a general immune defect. Chronic microbial infections (Option D): May trigger or worsen autoimmune responses but are not the primary cause of RA.

Only about 10% of patients with hyperuricemia develop clinical gout. Other factors contribute symptomatic gout: Age of the individual and duration of the hyperuricemia. Gout usually appears after 20 to 30 years of hyperuricemia. Genetic predisposition. In addition to the well-defined X-linked abnormalities of HGPRT, polymorphisms in genes involved with urate or ion transport and possibly inflammation are also associated with gout. Alcohol consumption. • Obesity. • Drugs (e.g., thiazides) that reduce excretion of urate Reference: Robbins, 10 th edition, page number- 824

Benign skeletal muscle tumor is rhabdomyoma. In heart, it is associated with tuberous sclerosis and show spider cells. Reference: Robbins Basic Pathology, 10 th ed, Pg: 192.

Ccp antibodies, also called anti-ccp antibodies, are a type of antibody called autoantibodies. Antibodies and autoantibodies are proteins made by the immune system. Antibodies protect you from disease by fighting foreign substances like viruses and bacteria. Reference: https://www.healthline.com/health/rheumatoid-arthritis/rheumatoid-arthritis-test#takeaway

Embryonal rhabdomyosarcoma. In the four options provided, all four show morphology of a round cell tumor. However, Desmin positivity is seen only in cases of rhabdomyosarcoma. Rhabdomyosarcoma is a malignant mesenchymal tumor with skeletal muscle differentiation. Three subtypes are alveolar (20%), embryonal (60%), and pleomorphic (20%). In embryonal rhabdomyosarcoma, the tumor cells mimic skeletal muscle at various stages of embryogenesis and consist of sheets of both primitive round and spindled cells in a myxoid stroma. Immunohistochemistry for desmin and myogenin confirms the rhabdomyoblastic differentiation. Reference: Robbins & Cotran Pathologic Basis of Diseases 10 th edition Chapter 26, pg 1212

REACTIVE ARTHRITIS, FORMERLY KNOWN AS REITER'S SYNDROME, IS A CONDITION THAT CAUSES INFLAMMATION (REDNESS AND SWELLING) IN VARIOUS PLACES IN THE BODY. IT USUALLY DEVELOPS FOLLOWING AN INFECTION, AND IN MOST CASES CLEARS UP IN A FEW MONTHS WITHOUT CAUSING LONG-TERM PROBLEMS. Reference: Robbins, 10 th edition, page number - 822

Ans. is `d' i.e., Highly radiosensitive Desmoid tumour is an aggressive fibromatosis or musculoaponeurotic fibromatosis is a monoclonal fibroblastic proliferation arising in musculoaponeurotic structures. Histologically these tumours are consist of spindle shaped cells in collagenous matrix and lack the pleomorphic, atypical or hyperchromatic nuclei of malignancy. A minority of desmoid tumours are associated with Gardener syndrome and mutations of familial adenomatous polyposis (FAP) gene. Most spontaneous desmoid tumours are associated with mutations of beta-catenin gene.