INI-CET 2023 - Pathology Practice Questions

Q: Order of drawing blood in vacutainers should be in the following sequence to prevent contamination?

Blue, Red, Violet, Grey. ***Blue, Red, Violet, Grey*** - This sequence follows the **CLSI (Clinical and Laboratory Standards Institute) order of draw** guidelines, which are critical for preventing **cross-contamination** between additives of different vacutainers. - The order starts with tubes for **coagulation studies** (blue top with sodium citrate), followed by serum tubes (red top), EDTA tubes (violet top for hematology), and finally glycolytic inhibitor tubes (grey top for glucose). - This prevents tissue thromboplastin contamination and anticoagulant carryover that could affect laboratory test results. *Grey, Blue, Red, Violet* - This order is incorrect as it places the **grey top tube** (containing fluoride/oxalate) first, which could contaminate subsequent tubes with its additives and affect tests. - The **blue top tube** for coagulation studies should come early in the sequence to minimize tissue thromboplastin contamination. *Blue, Violet, Red, Grey* - This sequence is incorrect because the **violet top tube** (EDTA) is placed before the **red top tube** (serum). - **EDTA contamination** can chelate calcium and other cations, interfering with chemistry tests performed on serum in the red top tube. *Red, Blue, Violet, Grey* - This order is incorrect as the **red top tube** is placed first, followed by the **blue top tube** (citrate). - The blue top tube should precede tubes with clot activators to **prevent tissue thromboplastin** from contaminating coagulation samples, which would lead to falsely shortened clotting times.

Q: A 14 year old male presents with mushroom like tumor in the distal femur for past 2 years. Which of the following features suggest malignant transformation?

Cartilage thickness $>2 \mathrm{~cm}$. ***Cartilage thickness >2 cm*** - A **cartilage cap thickness greater than 2 cm** in an osteochondroma in an adult (or >3 cm in children) is a strong indicator of **malignant transformation** into a secondary peripheral **chondrosarcoma**. [2], [3] - **Key imaging finding:** Cartilage cap measured on MRI or CT scan - Other features suggesting malignant transformation include continued growth after skeletal maturity, new or increasing pain, cortical destruction, and new soft tissue mass. [2], [3] *Presence of cartilage cap* - All osteochondromas have a cartilage cap by definition - this is a normal feature, not a sign of malignancy. [1] - The **thickness** of the cap, not its presence, is what matters. *Location in metaphysis* - Osteochondromas typically arise from the metaphysis near the growth plate - this is a normal location. [3] - Location alone does not indicate malignant transformation. *Size less than 1 cm* - Small size suggests a benign, stable lesion. - Malignant transformation is suggested by **increasing size** and growth after skeletal maturity, not small size. [2] **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Bones, Joints, and Soft Tissue Tumors, p. 1202. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Osteoarticular And Connective Tissue Disease, pp. 672-673. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Bones, Joints, and Soft Tissue Tumors, pp. 1202-1204.

Q: Abnormal accumulation of misfolded protein is seen in?

Creutzfeldt-Jakob disease. ***Creutzfeldt-Jakob disease*** - This is a neurodegenerative disease characterized by the accumulation of **abnormally folded prion proteins (PrPSc)** in the brain, leading to spongiform encephalopathy [1]. - The misfolding of normal cellular prion protein (PrPC) into its infectious and pathogenic form is central to the disease's pathology [2]. *Nephritic syndrome* - This syndrome is characterized by inflammation of the **glomeruli** in the kidneys, leading to hematuria, proteinuria, and hypertension. - It involves immune complex deposition and inflammation, not primarily the accumulation of misfolded proteins. *Sickle cell anemia* - This is a **genetic blood disorder** caused by a mutation in the beta-globin gene, leading to abnormal **hemoglobin S**. - While hemoglobin S can polymerize and deform red blood cells, it is not considered a disease of generalized misfolded protein accumulation in the same sense as prion diseases. *Megaloblastic anemia* - This condition is caused by impaired **DNA synthesis**, often due to **vitamin B12 or folate deficiency**, leading to large, immature red blood cells. - The pathology involves defective cell division and maturation, not the accumulation of misfolded proteins. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1284-1286. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Manifestations Of Central And Peripheral Nervous System Disease, pp. 712-713.

Question 1

Order of drawing blood in vacutainers should be in the following sequence to prevent contamination?

Accepted Answer

Blue, Red, Violet, Grey

Answer

Grey, Blue, Red, Violet

Answer

Blue, Violet, Red, Grey

Answer

Red, Blue, Violet, Grey

Question 2

All of the following are tests done for Turner mosaic screening except?

Accepted Answer

Serum FSH

Answer

Karyotype

Answer

FISH

Answer

Buccal smear

Question 3

A 14 year old male presents with mushroom like tumor in the distal femur for past 2 years. Which of the following features suggest malignant transformation?

Accepted Answer

Cartilage thickness $>2 \mathrm{~cm}$

Answer

Presence of cartilage cap

Answer

Location in metaphysis

Answer

Size less than 1 cm

Question 4

Abnormal accumulation of misfolded protein is seen in?

Accepted Answer

Creutzfeldt-Jakob disease

Answer

Nephritic syndrome

Answer

Sickle cell anemia

Answer

Megaloblastic anemia

INI-CET 2023 — Pathology