INI-CET 2015 — Pathology

Q: The following is the FITC for IgG stained kidney specimen. What is this suggestive of?

SLE. ***SLE*** - **Lupus nephritis** (a kidney manifestation of SLE) often shows a "full house" immunofluorescence pattern, including **IgG deposition**, along with IgA, IgM, C3, and C1q [1]. - The presence of **IgG staining** in a kidney biopsy is a common finding in various forms of lupus nephritis, such as diffuse proliferative glomerulonephritis [1,5]. *Buerger's disease* - This is a **vasculitis** primarily affecting small and medium-sized arteries and veins, typically in the limbs. - It does **not primarily involve the kidneys** with IgG deposition and is not diagnosed via kidney biopsy immunofluorescence. *Goodpasture syndrome* - Characterized by **linear deposition of IgG** along the glomerular basement membrane (GBM) on immunofluorescence. - While it involves IgG, the question implies a more general IgG staining, and Goodpasture's has a very specific **linear pattern**, which is distinct from the granular or mesangial patterns often seen in SLE [2]. *Membranous glomerulonephritis* - This condition is characterized by **granular subepithelial deposits of IgG and C3** along the glomerular basement membrane [1]. - While it involves IgG, the question's image (if implied) would likely show a more diffuse, granular pattern, and SLE can also present with IgG, but often with other immune complex components, making SLE a broader and often more complex picture [2]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 532-533. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, p. 911. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 230-232. [Practice more Pathology PYQs on OnCourse]

Q: The following microscopic appearance is that of a schwannoma which most commonly involves the cerebellopontine angle. What does the area marked with the arrow represent?

Antony B pattern. ***Antony B pattern-Verocay cells*** - The area marked with the arrow represents **Antony B pattern**, which is characterized by **hypocellularity** and a **myxoid matrix** [1]. - **Verocay bodies** are specific to schwannomas and are formed by palisading nuclei surrounding an anucleate zone, typically found within the **Antony A pattern** [1]. *Antony A pattern* - **Antony A pattern** is characterized by **dense cellularity** with palisading nuclei and often contains **Verocay bodies** [1]. - This pattern is typically more organized and compact compared to the area shown. *Antony C pattern-Verocay cells* - There is no recognized **Antony C pattern** in the histological classification of schwannomas. - The primary patterns described are **Antony A** and **Antony B**. *Antony D pattern-Verocay cells* - Similar to Antony C, there is no recognized **Antony D pattern** in the histological classification of schwannomas. - This option is a distractor based on an incorrect classification. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Peripheral Nerves and Skeletal Muscles, p. 1250. [Practice more Pathology PYQs on OnCourse]

Q: Which urine crystals are shown in the figure below?

Calcium oxalate dihydrate crystals. ***Calcium oxalate dihydrate crystals*** - The crystals shown are **octahedral** in shape, resembling small **envelopes**, which is characteristic of calcium oxalate dihydrate crystals. - These crystals typically appear in **acidic urine** and are the most common type of crystals that can lead to **kidney stones**. - Found in conditions like hyperoxaluria, ethylene glycol poisoning, and vitamin C excess. *Incorrect: Triple phosphate crystals* - Also known as **struvite crystals**, these have a characteristic **"coffin lid"** appearance. - Form in **alkaline urine** and are associated with urinary tract infections caused by urease-producing bacteria. *Incorrect: Uric acid crystals* - Appear as **rhomboid** or **rosette-shaped** crystals in **acidic urine**. - Associated with hyperuricemia, gout, and tumor lysis syndrome. *Incorrect: Cystine crystals* - Have a distinctive **hexagonal** shape and appear in acidic urine. - Pathognomonic for **cystinuria**, an inherited disorder of amino acid transport. *Incorrect: Calcium oxalate monohydrate crystals* - Have a **dumbbell** or **oval** shape, distinct from the envelope-shaped dihydrate form. - Also associated with hyperoxaluria and ethylene glycol poisoning. [Practice more Pathology PYQs on OnCourse]

3 Previous Year Questions with Answers & Explanations

Questions

All Subjects Anesthesiology (2)Community Medicine (2)Dermatology (2)ENT (1)Forensic Medicine (1)Internal Medicine (1)Internal Medicine (1)Microbiology (5)Obstetrics and Gynecology (4)Pathology (3)Pathology (4)Pediatrics (2)Pharmacology (3)Radiology (4)Surgery (1)

The following is the FITC for IgG stained kidney specimen. What is this suggestive of?

The following microscopic appearance is that of a schwannoma which most commonly involves the cerebellopontine angle. What does the area marked with the arrow represent?

Which urine crystals are shown in the figure below?

INI-CET 2015 - Pathology INI-CET Practice Questions and MCQs

Question 1: The following is the FITC for IgG stained kidney specimen. What is this suggestive of?

A. SLE (Correct Answer)
B. Post-streptococcal glomerulonephritis
C. Goodpasture syndrome
D. Membranous glomerulonephritis
E. IgA nephropathy

Explanation: ***SLE*** - **Lupus nephritis** (a kidney manifestation of SLE) often shows a "full house" immunofluorescence pattern, including **IgG deposition**, along with IgA, IgM, C3, and C1q [1]. - The presence of **IgG staining** in a kidney biopsy is a common finding in various forms of lupus nephritis, such as diffuse proliferative glomerulonephritis [1,5]. *Buerger's disease* - This is a **vasculitis** primarily affecting small and medium-sized arteries and veins, typically in the limbs. - It does **not primarily involve the kidneys** with IgG deposition and is not diagnosed via kidney biopsy immunofluorescence. *Goodpasture syndrome* - Characterized by **linear deposition of IgG** along the glomerular basement membrane (GBM) on immunofluorescence. - While it involves IgG, the question implies a more general IgG staining, and Goodpasture's has a very specific **linear pattern**, which is distinct from the granular or mesangial patterns often seen in SLE [2]. *Membranous glomerulonephritis* - This condition is characterized by **granular subepithelial deposits of IgG and C3** along the glomerular basement membrane [1]. - While it involves IgG, the question's image (if implied) would likely show a more diffuse, granular pattern, and SLE can also present with IgG, but often with other immune complex components, making SLE a broader and often more complex picture [2]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 532-533. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, p. 911. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 230-232.

Question 2: The following microscopic appearance is that of a schwannoma which most commonly involves the cerebellopontine angle. What does the area marked with the arrow represent?

A. Antony A pattern
B. Antony B pattern (Correct Answer)
C. Antony C pattern-Verocay cells
D. Antony D pattern-Verocay cells
E. Verocay bodies

Explanation: ***Antony B pattern-Verocay cells*** - The area marked with the arrow represents **Antony B pattern**, which is characterized by **hypocellularity** and a **myxoid matrix** [1]. - **Verocay bodies** are specific to schwannomas and are formed by palisading nuclei surrounding an anucleate zone, typically found within the **Antony A pattern** [1]. *Antony A pattern* - **Antony A pattern** is characterized by **dense cellularity** with palisading nuclei and often contains **Verocay bodies** [1]. - This pattern is typically more organized and compact compared to the area shown. *Antony C pattern-Verocay cells* - There is no recognized **Antony C pattern** in the histological classification of schwannomas. - The primary patterns described are **Antony A** and **Antony B**. *Antony D pattern-Verocay cells* - Similar to Antony C, there is no recognized **Antony D pattern** in the histological classification of schwannomas. - This option is a distractor based on an incorrect classification. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Peripheral Nerves and Skeletal Muscles, p. 1250.

Question 3: Which urine crystals are shown in the figure below?

A. Triple phosphate crystals
B. Uric acid crystals
C. Cystine crystals
D. Calcium oxalate dihydrate crystals (Correct Answer)
E. Calcium oxalate monohydrate crystals

Explanation: ***Calcium oxalate dihydrate crystals*** - The crystals shown are **octahedral** in shape, resembling small **envelopes**, which is characteristic of calcium oxalate dihydrate crystals. - These crystals typically appear in **acidic urine** and are the most common type of crystals that can lead to **kidney stones**. - Found in conditions like hyperoxaluria, ethylene glycol poisoning, and vitamin C excess. *Incorrect: Triple phosphate crystals* - Also known as **struvite crystals**, these have a characteristic **"coffin lid"** appearance. - Form in **alkaline urine** and are associated with urinary tract infections caused by urease-producing bacteria. *Incorrect: Uric acid crystals* - Appear as **rhomboid** or **rosette-shaped** crystals in **acidic urine**. - Associated with hyperuricemia, gout, and tumor lysis syndrome. *Incorrect: Cystine crystals* - Have a distinctive **hexagonal** shape and appear in acidic urine. - Pathognomonic for **cystinuria**, an inherited disorder of amino acid transport. *Incorrect: Calcium oxalate monohydrate crystals* - Have a **dumbbell** or **oval** shape, distinct from the envelope-shaped dihydrate form. - Also associated with hyperoxaluria and ethylene glycol poisoning.