NEET-PG 2015 Practice Questions

Q: Rademecker complex in EEG is seen in -

SSPE. ***SSPE*** - **Subacute sclerosing panencephalitis (SSPE)** is a rare, chronic, progressive encephalopathy characterized by a distinctive EEG pattern known as the **Rademecker complex**. - The **Rademecker complex** (also called Rademecker complexes or periodic stereotyped complexes) consists of high-amplitude, generalized, polyphasic delta waves that occur periodically every 4-15 seconds. *Kuru* - **Kuru** is a transmissible spongiform encephalopathy (TSE) with neurological symptoms like ataxia and tremors, but it does not typically show the **Rademecker complex** on EEG [1]. - EEG abnormalities in Kuru are generally non-specific and may include diffuse slowing, but not periodic complexes [1]. *cCJD* - **Classic Creutzfeldt-Jakob disease (cCJD)**, a prion disease, often shows characteristic **periodic sharp wave complexes (PSWCs)** on EEG. - These PSWCs are typically biphasic or triphasic, occurring at a frequency of 0.5-2 Hz, and are distinct from the slower, high-amplitude Rademecker complexes seen in SSPE. *vCJD* - **Variant Creutzfeldt-Jakob disease (vCJD)**, unlike cCJD, rarely or never shows the characteristic **periodic sharp wave complexes (PSWCs)** on EEG. - EEG findings in vCJD are usually non-specific, often showing generalized slowing without the unique periodic complexes seen in SSPE or cCJD.

Q: Lafora's disease presents with?

Myoclonic epilepsy. ***Myoclonic epilepsy*** - Lafora disease is a rare, neurodegenerative inherited disorder characterized by **progressive myoclonic epilepsy**. - Patients typically experience spontaneous or reflex-induced **myoclonic seizures**, often accompanied by falls [1]. *G.T.C.S* - While generalized tonic-clonic seizures (GTCS) can occur in Lafora disease as the condition progresses, they are not the primary or defining seizure type [3]. - The hallmark presentation is **myoclonic epilepsy**, which may then evolve to include GTCS. *Petit mal epilepsy* - **Petit mal epilepsy**, also known as absence seizures, is characterized by brief, sudden lapses of consciousness without loss of postural tone [1]. - This is a distinct epilepsy syndrome and not the typical presentation of Lafora disease. *Partial seizures* - **Partial seizures** originate in a specific area of the brain and can be simple or complex [2]. - While some focal signs might be observed as the disease advances, Lafora disease is primarily a generalized epilepsy characterized by myoclonus [1].

Q: Commonest cause of nosocomial infection is

Staphylococci. ***Staphylococci*** - **Staphylococci**, particularly *Staphylococcus aureus* (including MRSA) and coagulase-negative staphylococci, are the **most common cause** of nosocomial infections according to current surveillance data from CDC, WHO, and Indian hospital studies. - They are the leading cause of **surgical site infections**, **catheter-related bloodstream infections**, **ventilator-associated pneumonia**, and **skin and soft tissue infections** in hospital settings. - Their ability to form biofilms on medical devices, antibiotic resistance (especially MRSA), and widespread colonization of healthcare workers and patients make them the predominant nosocomial pathogen. *Enterobacteriaceae* - The family **Enterobacteriaceae** (including *E. coli*, *Klebsiella*, *Enterobacter*) represents a major group of gram-negative nosocomial pathogens. - They are very common causes of **urinary tract infections**, **pneumonia**, and **bloodstream infections**, particularly associated with indwelling catheters and ventilators. - While collectively representing a large proportion of nosocomial infections, they are the **second most common** group after Staphylococci in most contemporary studies. *Pseudomonas* - *Pseudomonas aeruginosa* is an important nosocomial pathogen, particularly in **ventilator-associated pneumonia**, **burn infections**, and infections in immunocompromised patients. - It accounts for approximately 10-15% of nosocomial infections and is especially problematic due to its intrinsic antibiotic resistance. *Klebsiella* - **Klebsiella** (particularly *K. pneumoniae*) is a member of the Enterobacteriaceae family and an important individual pathogen causing **pneumonia** and **urinary tract infections** in healthcare settings. - While a common pathogen, it represents only a subset of both the Enterobacteriaceae family and overall nosocomial infections, making it less common than the entire Staphylococci group.

Q: Causative agents of "Vincent's angina"

Borrelia vincenti and Fusobacterium nucleatum. ***Borrelia vincenti and Fusobacterium nucleatum*** - **Vincent's angina**, also known as **acute necrotizing ulcerative gingivitis (ANUG)**, is polymicrobial and characteristically involves a synergistic infection of **spirochetes** (like *Borrelia vincenti*, now classified as *Treponema vincentii*) and **fusobacteria** (like *Fusobacterium nucleatum*). - These organisms thrive in an anaerobic environment, leading to the characteristic ulcerative and necrotic lesions of the gingiva and oral mucosa. - This synergistic infection produces the classic "fusospirochaetal" complex seen on microscopy. *Borrelia burgdorferi and Lactobacillus* - *Borrelia burgdorferi* is the causative agent of **Lyme disease**, a tick-borne illness causing systemic symptoms, not Vincent's angina. - *Lactobacillus* species are common commensal bacteria found in the oral cavity, gut, and vagina, and are not pathogenic in the context of Vincent's angina. *Leptospira and Treponema pallidum* - *Leptospira* species cause **leptospirosis**, a zoonotic disease with symptoms like fever, headache, and muscle aches, often affecting the kidneys and liver. - *Treponema pallidum* is the causative agent of **syphilis**, a sexually transmitted infection, which presents with different oral lesions (e.g., chancre, mucous patches) that are distinct from Vincent's angina. *Borrelia recurrentis and Bacteroides* - *Borrelia recurrentis* causes **relapsing fever**, characterized by recurrent episodes of fever and other systemic symptoms, transmitted by lice or ticks. - While *Bacteroides* are common anaerobic bacteria in the oral flora, they are not the primary synergistic pair specifically associated with the distinct clinical presentation of Vincent's angina, as are the spirochetes and fusobacteria.

Q: All the following are common nosocomial infections except:

Mycobacterium. ***Mycobacterium*** - **Mycobacterium** species are not typically considered common causes of **acute nosocomial infections** because they are slow-growing and usually cause chronic infections. - While healthcare workers or patients can acquire tuberculosis in healthcare settings, it is less common for *Mycobacterium* to be the cause of rapidly developing, typical healthcare-associated infections like pneumonia or bloodstream infections. *Staph. aureus* - **_Staphylococcus aureus_** is a very common cause of **nosocomial infections**, particularly **MRSA (methicillin-resistant *S. aureus*)**, leading to surgical site infections, bloodstream infections, and pneumonia. - It colonizes healthcare workers and patients, making it easily transmissible in hospital environments. *Enterobacteriaceae* - **Enterobacteriaceae** (e.g., _E. coli_, _Klebsiella_, _Enterobacter_) are frequently implicated in **nosocomial infections**, especially **urinary tract infections (UTIs)**, pneumonia, and bloodstream infections. - These bacteria are part of the normal flora but can cause serious infections when introduced into sterile sites or in immunocompromised patients. *P. aeruginosa* - **_Pseudomonas aeruginosa_** is a significant cause of **nosocomial infections**, particularly in intensive care units (ICUs) and among immunocompromised patients. - It is known for causing **ventilator-associated pneumonia (VAP)**, UTIs, and wound infections, often exhibiting multidrug resistance.

Q: What is luxatio erecta ?

Inferior shoulder dislocation. ***Inferior shoulder dislocation*** - Luxatio erecta is a rare type of shoulder dislocation where the humeral head is displaced **inferiorly** and the arm is fixed in an **elevated position**, often described as looking as if the patient is "waving hello." - This dislocation typically results from **hyperabduction** of the arm, forcing the humeral head out of the glenoid fossa. *Anterior shoulder dislocation* - This is the most common type of shoulder dislocation, where the humeral head is displaced **anteriorly** and **inferiorly** beneath the coracoid process. - The arm is typically held in **abduction** and **external rotation**, not a sustained elevation. *Posterior hip dislocation* - This involves the displacement of the **femoral head** out of the acetabulum in a **posterior direction**, often due to high-energy trauma dashboard injuries. - The leg typically presents in **internal rotation**, adduction, and flexion. *Anterior hip dislocation* - This less common hip dislocation involves the femoral head displacing **anteriorly** relative to the acetabulum. - The affected leg is usually held in **external rotation**, abduction, and slight flexion.

Q: Investigation of choice for confirming Henoch Schönlein Purpura is

Renal Biopsy. ***Renal Biopsy*** - **Biopsy (renal or skin)** showing **IgA deposition** is the **confirmatory investigation** for Henoch-Schönlein Purpura (HSP) when histological confirmation is needed [1]. - **Renal biopsy** demonstrates characteristic **IgA-dominant immune deposits** in the mesangium and glomerular capillaries, along with **mesangial proliferation** [1]. - While HSP is primarily a **clinical diagnosis** based on palpable purpura, age < 20 years, abdominal pain, and renal involvement, biopsy provides **definitive confirmation** in atypical presentations or when diagnosis is uncertain. - Immunofluorescence showing **IgA deposition** is the pathognomonic finding [1]. *Serum IgA levels* - Serum IgA levels may be elevated in approximately **50% of HSP cases**, but this is **neither sensitive nor specific**. - **Normal serum IgA does NOT exclude HSP**, making it unreliable as a confirmatory test. - Elevated IgA can occur in many other conditions (IgA nephropathy without vasculitis, liver disease, infections). - Provides only supportive evidence, not confirmation. *CRP levels* - **C-reactive protein (CRP)** is a **non-specific inflammatory marker** that may be elevated in HSP. - Cannot distinguish HSP from other inflammatory or infectious conditions. - Has no role in confirming the diagnosis. *DTPA* - **DTPA scan** assesses **renal perfusion and function** but does not provide diagnostic information about the underlying pathology. - Cannot detect the characteristic **IgA-mediated vasculitis** of HSP. - Not useful for confirming the diagnosis. **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. 526-527.

Q: Mechanism of action of thiazides is by -

Inhibiting Na+/Cl- symporter in DCT. **Inhibiting Na+/Cl- symporter in DCT** - Thiazide diuretics primarily act on the **distal convoluted tubule (DCT)** of the nephron [2]. - They inhibit the **Na+/Cl- symporter** (NCC channel) on the apical membrane, preventing reabsorption of sodium and chloride ions [1], [2]. *Inhibiting Na+K+2CI- in descending limb of loop of henle* - The descending limb of the loop of Henle is permeable to water but largely impermeable to solutes; there is no significant Na+K+2Cl- symporter activity here. - This mechanism describes the action of loop diuretics, but they act on the **ascending** limb, not the descending limb. *Inhibiting Na+K+2Cl- in ascending limb of loop of henle* - This mechanism describes the action of **loop diuretics** (e.g., furosemide, bumetanide) [3]. - Loop diuretics inhibit the **Na+K+2Cl- cotransporter (NKCC2)** in the thick ascending limb of the loop of Henle, leading to significant diuresis [3]. *Inhibiting Na+/Cl- symporter in PCT* - The **proximal convoluted tubule (PCT)** is primarily responsible for reabsorbing most of the filtered sodium, chloride, bicarbonate, and other solutes. - While sodium is reabsorbed in the PCT, it's mainly through Na+/H+ exchangers and other mechanisms, not a specific Na+/Cl- symporter that is targeted by thiazides [2].

Q: Most recently identified taste sensation is?

Umami. ***Umami*** - **Umami** is the most recently identified **fifth basic taste**, often described as a savory or meaty taste. - Its discovery and recognition as a distinct taste sensation occurred in the **early 20th century** by Kikunae Ikeda, who isolated glutamate from kombu. *Sour* - The sensation of **sourness** is one of the traditionally recognized basic tastes, identified much earlier than umami. - It is typically associated with **acids**, such as those found in lemons or vinegar. *Bitter* - **Bitterness** is another long-standing basic taste that serves an important protective function, often signaling potential toxins. - It is one of the earliest tastes understood and recognized, with receptors for a wide range of bitter compounds. *Sweet* - **Sweetness** is a fundamental and ancient taste, universally recognized as pleasurable and indicating energy-rich foods. - The perception of sweet taste, primarily from sugars, has been understood for centuries.

Q: Vibration sense is detected by ?

Deep receptors. ***Deep receptors*** - **Vibration sense** is primarily mediated by **Pacinian corpuscles** and **Meissner's corpuscles**, which are considered deep receptors. - **Pacinian corpuscles** are located in the **deep dermis** and **subcutaneous tissue** and are highly sensitive to **high-frequency vibration** (200-300 Hz). - **Meissner's corpuscles** in dermal papillae detect **lower frequency vibration** and are rapidly adapting mechanoreceptors. *Superficial receptors* - **Superficial receptors** like **Merkel cells** primarily detect **sustained touch** and **pressure**, providing information about texture. - While they contribute to tactile sensation, they are **slowly adapting** and not specialized for rapidly oscillating stimuli like vibration. *Free nerve endings* - **Free nerve endings** are unmyelinated or lightly myelinated nerve terminals that detect **pain**, **temperature**, and **crude touch**. - They are not specialized mechanoreceptors and lack the structural organization needed to transduce vibratory stimuli. *Nociceptors* - **Nociceptors** are specialized sensory receptors that detect **noxious (harmful) stimuli** and mediate the sensation of **pain**. - They respond to extreme temperatures, intense mechanical stress, or chemical irritants, not to non-painful vibration.

Question 1

Rademecker complex in EEG is seen in -

Accepted Answer

SSPE

Answer

Kuru

Answer

cCJD

Answer

vCJD

Question 2

Lafora's disease presents with?

Accepted Answer

Myoclonic epilepsy

Answer

G.T.C.S

Answer

Petit mal epilepsy

Answer

Partial seizures

Question 3

Commonest cause of nosocomial infection is

Accepted Answer

Staphylococci

Answer

Klebsiella

Answer

Enterobacteriaceae

Answer

Pseudomonas

Question 4

Causative agents of "Vincent's angina"

Accepted Answer

Borrelia vincenti and Fusobacterium nucleatum

Answer

Borrelia burgdorferi and Lactobacillus

Answer

Leptospira and Treponema pallidum

Answer

Borrelia recurrentis and Bacteroides

Question 5

All the following are common nosocomial infections except:

Accepted Answer

Mycobacterium

Answer

Staph. aureus

Answer

Enterobacteriaceae

Answer

P. aeruginosa

Question 6

What is luxatio erecta ?

Accepted Answer

Inferior shoulder dislocation

Answer

Anterior shoulder dislocation

Answer

Posterior hip dislocation

Answer

Anterior hip dislocation

Question 7

Investigation of choice for confirming Henoch Schönlein Purpura is

Accepted Answer

Renal Biopsy

Answer

Serum IgA levels

Answer

CRP levels

Answer

DTPA

Question 8

Mechanism of action of thiazides is by -

Accepted Answer

Inhibiting Na+/Cl- symporter in DCT

Answer

Inhibiting Na+K+2Cl- in ascending limb of loop of henle

Answer

Inhibiting Na+/Cl- symporter in PCT

Answer

Inhibiting Na+K+2Cl- in descending limb of loop of henle

Question 9

Most recently identified taste sensation is?

Accepted Answer

Umami

Answer

Sour

Answer

Bitter

Answer

Sweet

Question 10

Vibration sense is detected by ?

Accepted Answer

Deep receptors

Answer

Superficial receptors

Answer

Free nerve endings

Answer

Nociceptors

NEET-PG 2015

Internal Medicine

Microbiology

Orthopaedics

Pathology

Pharmacology

Physiology