Pathology
2 questionsMedulloblastoma arises exclusively from the cells of
Which one of the following statements is false about Xanthogranulomatous pyelonephritis in children?
NEET-PG 2015 - Pathology NEET-PG Practice Questions and MCQs
Question 971: Medulloblastoma arises exclusively from the cells of
- A. Immature embryonal cells (Correct Answer)
- B. Ependymal cells
- C. Neurons
- D. Spindle-shaped cells
Explanation: ***Immature embryonal cells*** - **Medulloblastoma** is a malignant **embryonal tumor** of the cerebellum, exclusively arising from primitive neuroectodermal cells. - These tumors are thought to originate from remnants of the **external granular layer** of the cerebellum or other primitive neuroectodermal cells. *Ependymal cells* - Tumors arising from **ependymal cells** are called **ependymomas**, which typically occur within the ventricles of the brain or spinal cord. - Ependymomas have distinct histological features and clinical behavior compared to medulloblastomas. *Neurons* - Tumors primarily composed of neurons or with significant neuronal differentiation include **gangliogliomas** and **central neurocytomas**. - **Medulloblastomas** largely consist of undifferentiated, small round cells with minimal evidence of neuronal maturation. *Spindle-shaped cells* - **Spindle-shaped cells** are characteristic of various tumor types, including some **gliomas** (e.g., pilocytic astrocytoma) or mesenchymal tumors. - While some medulloblastoma variants can show desmoplastic features, the hallmark cell type is a small, round, blue embryonal cell.
Question 972: Which one of the following statements is false about Xanthogranulomatous pyelonephritis in children?
- A. Clinical presentation in children is the same as in adults
- B. Boys are affected more frequently (Correct Answer)
- C. Often affects those younger than 8 years of age
- D. It affects the kidney diffusely more frequently than focally
Explanation: ***Boys are affected more frequently*** - This statement is **false** for xanthogranulomatous pyelonephritis (XGP) in children. XGP typically shows a **female predominance** in children, similar to adults. - The disease is more common in girls due to the higher incidence of **urinary tract infections** and **urinary obstruction** in females. *It affects the kidney diffusely more frequently than focally* - This statement is **true**. XGP predominantly presents as a **diffuse disease** affecting the entire kidney in approximately **80-90% of cases**. - **Focal XGP** (10-20% of cases) can occur and may mimic a renal tumor, but diffuse involvement is the classic and more common presentation in both adults and children [1]. *Clinical presentation in children is the same as in adults* - This statement is **true**. Children with XGP often present with similar symptoms to adults, including **fever**, **flank pain**, **recurrent urinary tract infections**, and a **palpable abdominal mass** [1]. - **Failure to thrive** and **anemia** are also common in pediatric cases, reflecting the chronic nature of the infection. *Often affects those younger than 8 years of age* - This statement is **true**. XGP, when it occurs in children, often presents in the **younger age group**, typically before 8 years of age. - This demographic observation highlights the importance of considering XGP in young children with persistent urinary tract symptoms and imaging abnormalities. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, pp. 939-940.
Pediatrics
8 questionsWhich of the following statements about encephalocoele is false?
Which of the following statements about cephalhematoma is correct?
Which of the following is NOT a symptom of Kwashiorkor?
What is the maintenance fluid requirement in a 6 kg child ?
Most common type of TAPVC is -
Which of the following statements about shock in children is correct?
At what rate should dopamine be administered for inotropic support in a severely dehydrated child?
Which test is used to diagnose congenital syphilis in a newborn born to a syphilitic mother?
NEET-PG 2015 - Pediatrics NEET-PG Practice Questions and MCQs
Question 971: Which of the following statements about encephalocoele is false?
- A. It is a neural tube defect
- B. Common in the parietal region (Correct Answer)
- C. Can be associated with hydrocephalus
- D. It is protrusion of neural tissue through a defect
Explanation: ***Common in the parietal region*** - This statement is **false** because encephaloceles are **rarely found in the parietal region** (only 10-15% of cases). - **Occipital encephaloceles** are most common in Western populations (75-80%), while **frontal/sincipital encephaloceles** are most common in Southeast Asia including India (40-60%). - **Parietal encephaloceles** represent only a small minority of cases globally, making this statement incorrect. *It is a neural tube defect* - **Encephalocele** is indeed a type of **neural tube defect (NTD)**, resulting from incomplete closure of the neural tube during embryonic development. - Specifically, it involves a defect in the skull that allows for protrusion of brain tissue and/or meninges. *Can be associated with hydrocephalus* - **Hydrocephalus**, or the accumulation of cerebrospinal fluid in the brain, is a known complication and associated condition with encephaloceles. - The abnormal brain development and structural defects can disrupt normal CSF flow and absorption, particularly with posterior encephaloceles. *It is protrusion of neural tissue through a defect* - This is the defining characteristic of an **encephalocele**: the **herniation of intracranial contents**, such as brain tissue, meninges, or both, through a congenital **bony defect** in the skull. - The contents of the sac can vary (meninges only = meningocele; brain tissue included = meningoencephalocele), influencing clinical presentation and prognosis.
Question 972: Which of the following statements about cephalhematoma is correct?
- A. It is hemorrhage between the skull and periosteum (Correct Answer)
- B. It is hemorrhage within the subcutaneous tissue around the skull
- C. It is type of subdural hemorrhage
- D. It is subperiosteal bleeding in the skull
Explanation: ***It is hemorrhage between the skull and periosteum*** - A **cephalhematoma** is defined as a collection of blood between the **periosteum** and the underlying **skull bone** (subperiosteal). - Its boundaries are limited by the suture lines because the periosteum is firmly attached at these junctions, preventing blood from crossing. *It is hemorrhage within the subcutaneous tissue around the skull* - This description corresponds to a **caput succedaneum**, which involves **edema and hemorrhage** in the subcutaneous tissue, rather than between the skull and periosteum. - Unlike a cephalhematoma, a **caput succedaneum** can cross suture lines and is typically present at birth. *It is type of subdural hemorrhage* - A **subdural hemorrhage** involves bleeding between the **dura mater** and the **arachnoid mater** within the cranial vault. - This type of hemorrhage is a **neurological emergency** and is distinct from a cephalhematoma, which is an external scalp injury. *It is subperiosteal bleeding in the skull* - While this statement is technically correct (subperiosteal means under the periosteum), the **standard definition** specifically states "between the periosteum and the skull bone." - The distinction is important: **subperiosteal** could theoretically include bleeding within the periosteum itself, whereas the precise location is in the **potential space** between periosteum and bone. - Option A is more precise and is the preferred medical definition.
Question 973: Which of the following is NOT a symptom of Kwashiorkor?
- A. Hypertension (Correct Answer)
- B. Hair changes and depigmentation
- C. Edema
- D. Growth retardation
Explanation: ***Hypertension*** - **Hypertension** is generally **NOT a direct symptom** of Kwashiorkor; rather, children with Kwashiorkor often have **low blood pressure** due to overall cardiovascular system depression. - While chronic malnutrition can have various systemic effects, elevated blood pressure is not a characteristic clinical feature of this condition. - This is the correct answer as the question asks what is NOT a symptom. *Hair changes and depigmentation* - This is a **classic symptom** of Kwashiorkor, characterized by sparse, brittle hair that may be discolored (e.g., reddish or yellowish - "flag sign"). - These changes reflect the severe protein deficiency interfering with hair follicle function and melanin production. *Edema* - **Edema**, particularly in the lower extremities and face, is a **hallmark symptom** of Kwashiorkor, caused by severe protein deficiency leading to decreased oncotic pressure. - This results in fluid shifting from the intravascular space into the interstitial space. *Growth retardation* - **Growth retardation** (stunting) is a common and severe symptom of Kwashiorkor, reflecting the long-term impact of inadequate protein and energy intake on physical development. - Both height and weight are significantly below age-appropriate norms.
Question 974: What is the maintenance fluid requirement in a 6 kg child ?
- A. 240 ml/day
- B. 600 ml/day (Correct Answer)
- C. 300 ml/day
- D. 1200 ml/day
Explanation: **600 ml/day** - The **Holliday-Segar formula** is used to calculate maintenance fluid requirements. For the first 10 kg of body weight, the requirement is 100 ml/kg/day. - For a 6 kg child, the calculation is 6 kg * 100 ml/kg/day = **600 ml/day**. *240 ml/day* - This value is significantly **lower** than the recommended maintenance fluid for a 6 kg child, which would lead to **dehydration**. - It does not align with the standard Holliday-Segar formula for this weight. *300 ml/day* - This amount is **insufficient** for a 6 kg child's daily maintenance fluid needs and would risk **hypovolemia**. - It represents roughly half of the calculated requirement based on standard pediatric guidelines. *1200 ml/day* - This volume is significantly **higher** than the maintenance fluid requirement for a 6 kg child and could lead to **fluid overload** and hyponatremia. - This calculation might be appropriate for a much heavier child or in situations of increased fluid loss.
Question 975: Most common type of TAPVC is -
- A. Supracardiac (Correct Answer)
- B. Cardiac
- C. Infracardiac
- D. Multiple
Explanation: ***Supracardiac*** - This is the **most common type** of Total Anomalous Pulmonary Venous Connection (TAPVC), accounting for about 50% of cases. - Pulmonary veins drain into a **common vertical vein** that ascends to connect with the **innominate vein** or superior vena cava. *Cardiac* - In this type, the pulmonary veins drain directly into the **right atrium** or a coronary sinus. - It is relatively less common than the supracardiac type. *Infracardiac* - This is the **least common** and most severe type, where the pulmonary veins drain below the diaphragm, typically into the portal vein, ductus venosus, or inferior vena cava. - It is often associated with **pulmonary venous obstruction**, leading to cyanosis and pulmonary hypertension. *Multiple* - While it is possible to have anomalous drainage sites, **multiple sites** draining into different systemic veins are less common than a single primary site for TAPVC. - TAPVC is typically classified into specific anatomic types rather than 'multiple' as a primary category.
Question 976: Which of the following statements about shock in children is correct?
- A. Tachycardia is a sensitive indicator of shock in children. (Correct Answer)
- B. Mottling of extremities is an early sign of shock.
- C. Confusion and stupor are early signs of shock.
- D. Respiratory rate is a more sensitive indicator of shock than heart rate.
Explanation: ***Tachycardia is a sensitive indicator of shock in children.*** - **Tachycardia** is often the first and most reliable sign of **compensated shock** in children, as their cardiovascular system initially maintains cardiac output by increasing heart rate. - Children have a remarkable ability to compensate for significant fluid loss, and an elevated heart rate helps maintain **perfusion** before blood pressure drops. *Mottling of extremities is an early sign of shock.* - **Mottling** of extremities is typically a sign of **decompensated shock** and indicates significant vasoconstriction and poor tissue perfusion. - It is a **late sign** that suggests the child's compensatory mechanisms are failing. *Confusion and stupor are early signs of shock.* - **Altered mental status**, such as confusion or stupor, usually indicates **severe shock** and reduced cerebral perfusion. - These are generally **late signs** of shock, appearing after initial compensatory mechanisms have failed. *Respiratory rate is a more sensitive indicator of shock than heart rate.* - While **tachypnea** can be present in shock due to metabolic acidosis or compensatory mechanisms, **tachycardia** is a more consistently sensitive and earlier indicator of circulatory compromise. - Respiratory changes can also be influenced by other factors like pain, fever, or respiratory illness, making heart rate a more specific initial marker for shock.
Question 977: At what rate should dopamine be administered for inotropic support in a severely dehydrated child?
- A. 0.1-0.5 microgram/kg/min
- B. 1-5 microgram/kg/min (Correct Answer)
- C. 1-5 mg/kg/min
- D. 10-15 mg/kg/min
Explanation: ***1-5 microgram/kg/min*** - This dosage range of **dopamine** primarily targets **beta-1 adrenergic receptors**, leading to **increased myocardial contractility** (inotropic effect) and improved cardiac output. - It is appropriate for managing **hypotension** and poor perfusion in a severely dehydrated child after initial **fluid resuscitation** has been attempted but was insufficient. *0.1-0.5 microgram/kg/min* - This very low dose range of dopamine primarily stimulates **dopaminergic receptors** in the renal and mesenteric vascular beds. - Its main effect is **vasodilation** in these areas, which increases blood flow to the kidneys and gut, but it provides minimal to no **inotropic support**. *1-5 mg/kg/min* - This dosage is significantly too high, as it is in milligrams rather than micrograms. - Administering dopamine at this rate would lead to severe **toxicity**, including profound **tachycardia**, ventricular arrhythmias, and extreme **vasoconstriction**. *10-15 mg/kg/min* - This dopamine dosage is also excessively high, again due to being in milligrams per minute rather than micrograms per minute. - Such a dose would be **lethal**, causing catastrophic cardiovascular collapse due to overwhelming **alpha-adrenergic stimulation** and severe arrhythmias.
Question 978: Which test is used to diagnose congenital syphilis in a newborn born to a syphilitic mother?
- A. Detection of IgG
- B. ZN staining
- C. Detection of IgM (Correct Answer)
- D. FTA-ABS test
Explanation: ***Detection of IgM*** - The presence of **IgM antibodies** in a newborn suggests active infection because maternal IgM does not cross the placenta. - This indicates the newborn's immune system has produced its own antibodies in response to *Treponema pallidum* infection. *Detection of IgG* - **Maternal IgG antibodies can cross the placenta**, so detecting IgG in a newborn does not differentiate between passive transfer from the mother and active newborn infection. - While total IgG might be elevated due to infection, specific IgM is a more reliable indicator of active congenital syphilis. *ZN staining* - **Ziehl-Neelsen (ZN) staining** is used to identify **acid-fast bacteria**, such as *Mycobacterium tuberculosis*, not spirochetes like *Treponema pallidum*. - *Treponema pallidum* is typically visualized using darkfield microscopy or silver stains due to its thin, helical shape. *FTA-ABS test* - The **Fluorescent Treponemal Antibody Absorption (FTA-ABS)** test detects specific antibodies against *Treponema pallidum* but primarily measures IgG, which can be maternally transferred. - While it confirms exposure, an IgM-specific FTA-ABS would be more definitive for congenital syphilis, but the general FTA-ABS test alone is not sufficient to diagnose active infection in a newborn.