Regulation and Integration-II Pathology Practice Flashcards

This set covers pathology lectures on Diabetes Mellitus, Pancreatic disorders, Adrenal neoplasms, MEN syndromes, and various Renal diseases including glomerular, tubular, and vascular conditions.

How is Diabetes Mellitus defined according to the lecture notes?

A group of metabolic disorders sharing the common feature of Hyperglycemia caused by defects in insulin secretion, insulin action, or most commonly both.

What are the four diagnostic criteria for Diabetes Mellitus according to the ADA and WHO?

1. Fasting plasma glucose $\ge 126\,mg/dL$, 2. Random plasma glucose $\ge 200\,mg/dL$ (with classic signs), 3. 2-hour plasma glucose $\ge 200\,mg/dL$ during an OGTT with a $75\,g$ loading dose, 4. Glycated hemoglobin (HbA1c) level $\ge 6.5\%$.

What are the glycated hemoglobin (HbA1c) percentage thresholds for a Prediabetes diagnosis?

$5.7\%$ to $6.4\%$.

Which HLA haplotypes are most strongly associated with Type 1 Diabetes in whites?

HLA-DR3 or HLA-DR4.

What are the three stages of the 'Classic triad' of Diabetes symptoms?

Polyuria, Polydipsia, and Polyphagia.

In the polyol pathway of chronic diabetes complications, what enzyme converts glucose to sorbitol?

Aldose reductase (using NADPH as a cofactor).

What is the characteristic microscopic finding in the pancreas of a patient with Type 2 Diabetes?

Reduction in islet cell mass accompanied by amyloid deposition.

What is the most common cause of death in diabetic patients due to macrovascular disease?

Myocardial infarction (precipitated by accelerated atherosclerosis).

What are the three microscopic lesions encountered in Diabetic Nephropathy?

1. Glomerular lesions (GBM thickening), 2. Diffuse mesangial sclerosis, 3. Nodular glomerulosclerosis (Kimmelstiel-Wilson disease).

What is the 'Glove and stocking' pattern in diabetic patients?

A pattern of distal symmetric polyneuropathy of the lower extremities that eventually involves the upper extremities.

What are the two most common etiologies for Acute Pancreatitis in the United States?

Biliary tract disease (Gall stones) and Alcoholism.

How is Trypsinogen normally activated in the duodenum?

It is cleaved and activated by duodenal enteropeptidase (enterokinase) to become Trypsin.

What are the basic morphologic features of Acute Hemorrhagic Pancreatitis?

Vascular injury with interstitial hemorrhage, fat necrosis (chalky-white areas), and proteolytic destruction of the parenchyma.

What is the 'specific and sensitive' marker commonly used to support a diagnosis of Acute Pancreatitis?

Serum Lipase (at $3 \times$ the upper limit of normal).

What is 'Thyroidization' of the renal tubules and where is it seen?

A microscopic finding where renal tubules are dilated and filled with pink hyaline casts resembling thyroid colloid; it is seen in Chronic Pyelonephritis.

Which genetic mutation is present in over $90\%$ of pancreatic cancers?

KRAS point mutations (on chromosome 12p).

What is the 'Courvoisier sign' and what condition does it typically indicate?

A palpably enlarged, non-tender gall bladder with jaundice; it typically indicates cancer of the head of the pancreas obstructing the common bile duct.

What is an Insulinoma and what is its characteristic clinical finding?

A $\beta$-cell tumor of the pancreatic islets that secretes insulin; it is characterized by clinically significant hypoglycemia (blood sugar level $< 50\,mg/dL$).

What triad of symptoms characterizes Zollinger-Ellison syndrome (Gastrinoma)?

Severe peptic ulcers (often jejunal), hypersecretion of gastric acid, and pancreatic islet cell lesions.

The 'Rule of 10s' is associated with which adrenal tumor?

Pheochromocytoma ($10\%$ extra-adrenal, $10\%$ bilateral, $10\%$ malignant, $10\%$ not associated with hypertension).

Describe the Zellballen pattern found in Pheochromocytoma.

Nests of polygonal to spindle-shaped chromaffin cells surrounded by supporting sustentacular cells and a rich vascular network.

What are Homer-Wright pseudorosettes and in which tumor are they characteristic?

Characteristic arrangements of small, round blue neuroblasts around a central faintly eosinophilic neurofibrillary background (neuropil), seen in Neuroblastoma.

What are the components of Multiple Endocrine Neoplasia Type 1 (MEN-1), also known as Wermer syndrome?

The '3 Ps': Pituitary (adenomas), Parathyroid (hyperplasia/adenomas), and Pancreas (hyperplasia/adenomas/carcinomas).

Which germline mutation is associated with Multiple Endocrine Neoplasia Type 2 (MEN-2A and 2B)?

RET proto-oncogene (gain of function).

Define the classic clinical signs of Nephrotic Syndrome.

Heavy proteinuria ($> 3.5\,g/day$), Hypoalbuminemia ($< 3\,g/dL$), Generalized edema, Hyperlipidemia, and Lipiduria.

What is the hallmark electron microscopy finding for Minimal Change Disease (MCD)?

Diffuse effacement of podocyte foot processes with loss of intervening slit diaphragms.

What morphology is described by the 'Spike and Dome' pattern in Membranous Glomerulonephritis?

Thickening of the GBM due to subepithelial Ig deposits separated by small, spike-like protrusions of GBM matrix.

What is the most common cause of Nephrotic Syndrome in children aged 1-7?

Minimal Change Disease (MCD).

Describe the definitive morphology of Rapidly Progressive Glomerulonephritis (RPGN).

Crescent moon-shaped fibrin-containing deposits within the Bowman’s capsule, formed by proliferation of epithelial cells and leukocytes.

What are the two clinical features of Goodpasture syndrome?

Recurrent hemoptysis and renal failure (Pulmonary-Renal syndrome), caused by anti-GBM antibodies.

Which disease is characterized by IgA deposits in the glomerular mesangium and is the most common glomerulonephritis worldwide?

IgA Nephropathy (Berger disease).

What are 'Muddy brown granular casts' indicative of in a clinical urinalysis?

Acute Tubular Injury (ATI) / Acute Tubular Necrosis (ATN) in the maintenance phase.

What is 'Grain leather appearance' regarding renal pathology?

The gross morphology of the kidneys in Benign Nephrosclerosis, characterized by a finely granular surface.

Which condition is defined by severe hypertension ($> 180/120\,mmHg$) and 'onion skin' hyperplastic arteriosclerosis?

Malignant Nephrosclerosis.

What is the Pentad of findings for Thrombotic Thrombocytopenic Purpura (TTP)?

Fever, Neurologic symptoms, Microangiopathic hemolytic anemia (MAHA), Thrombocytopenia, and Renal dysfunction.

What is the most common type of Renal Cell Carcinoma (RCC)?

Clear cell carcinoma ($80\%$ of cases), often associated with mutations in the VHL tumor suppressor gene.

Name the characteristic 'Triphasic' features of a Wilms Tumor (Nephroblastoma).

1. Blastema (sheets of small round blue cells), 2. Immature stroma, 3. Epithelial differentiation (abortive tubules and glomeruli).

What is the most significant environmental risk factor for Urothelial Carcinoma of the urinary bladder?

Smoking.

Distinguish between Primary and Secondary Nephrotic Syndrome causes in adults and children.

In children, $95\%$ are primary glomerular diseases (like MCD). In adults, causes are commonly secondary to systemic diseases (MAIDS: Malignancy, Amyloidosis, Infection, Diabetes, SLE).

What is the effect of sorbitol accumulation in the lens of the eye in diabetic patients?

It increases osmotic pressure and leads to water influx, contributing to cataracts.