NEET-PG 2013 Practice Questions

Q: Most common mode of transmission of nosocomial infection is -

Hand contact. ***Hand contact*** - **Direct contact** with healthcare workers' contaminated hands is the primary way pathogens are transferred between patients in a healthcare setting. - Failure to perform adequate **hand hygiene** between patient contacts is the single most important factor contributing to nosocomial infection transmission. *Droplet infection* - While droplet transmission can cause nosocomial infections, especially for respiratory viruses, it is not the most common mode of transmission for the overall burden of healthcare-associated infections. - **Droplets** usually travel short distances and deposit on mucous membranes of the nose, mouth, or eyes of a susceptible host. *Blood and blood products* - Transmission through **blood and blood products** is a significant concern for specific infections (e.g., HIV, hepatitis B/C), but the incidence is relatively low due to stringent screening and safety protocols. - This mode accounts for a small fraction of overall nosocomial infections compared to contact transmission. *Contaminated water* - **Contaminated water** can lead to outbreaks (e.g., *Legionella*, *Pseudomonas*), especially in immunocompromised patients, but it is not the most frequent mode of transmission on a day-to-day basis across all types of nosocomial infections. - Healthcare facilities implement measures to ensure water safety, limiting this as the primary route.

Q: The BEINGS Model of disease causation does not include which of the following factors?

Spiritual factors. ***Spiritual factors*** - The **BEINGS model** does not include \"Spiritual factors\" as one of its components. - The BEINGS acronym stands for: **B**iological, **E**nvironmental, **I**mmunological, **N**utritional, **G**enetic, and **S**ocial factors. - While spirituality can influence health outcomes, it is not a formal component of this epidemiological model. *Religious factors* - Religious factors, like spiritual factors, are also not explicitly part of the BEINGS model. - However, religious practices and beliefs may be considered as part of **social factors** (the \"S\" in BEINGS) in some contexts. - This option is less clearly excluded than spiritual factors. *Social factors* - The \"**S**\" in BEINGS specifically stands for **Social factors**, not spiritual factors. - Social factors include community networks, socioeconomic status, cultural practices, and social support systems. - These are well-established determinants of health and disease causation. *Nutritional factors* - The \"**N**\" in BEINGS stands for **Nutritional factors**. - Nutrition plays a critical role in disease causation, affecting immunity, growth, and susceptibility to various diseases. - Deficiencies or excesses in nutrition can lead to a wide range of health problems.

Q: Which of the following viral diseases is least commonly reported in India?

Lassa fever. ***Lassa fever*** - **Lassa fever** is endemic to West Africa, with the **multimammate rat** being its primary reservoir. - Cases of Lassa fever are **extremely rare** in India, primarily limited to travel-related instances due to the geographical distribution of the disease and its vector. *Japanese B encephalitis* - **Japanese B encephalitis (JBE)** is a significant public health concern in India, particularly in endemic regions. - It is a mosquito-borne viral disease, and **vaccination programs** are ongoing to control its spread. *KFD* - **Kyasanur Forest Disease (KFD)** is an endemic viral hemorrhagic fever primarily found in the **Karnataka state of India**. - It is transmitted by **ticks**, making it a regionally significant but recognized viral disease within India. *Dengue* - **Dengue** is one of the most commonly reported and widespread viral diseases in India. - It is a **mosquito-borne** illness with frequent outbreaks occurring across various parts of the country.

Q: What is the most common cause of ASOM?

Pneumococci. ***Pneumococci*** - **_Streptococcus pneumoniae_ (Pneumococci)** is the **most common bacterial cause** of Acute Suppurative Otitis Media (ASOM) in all age groups, particularly in young children. - It accounts for an estimated 25-50% of all ASOM cases, often leading to significant inflammation and **purulent discharge**. *Meningococci* - **_Neisseria meningitidis_ (Meningococci)** is rarely a cause of ASOM. - It is primarily known for causing **meningitis** and **sepsis**, not typically middle ear infections. *H. influenzae* - **_Haemophilus influenzae_ (non-typable)** is the **second most common cause** of ASOM, accounting for 20-40% of cases. - While significant, it is generally less prevalent than _Streptococcus pneumoniae_. *Moraxella catarrhalis* - **_Moraxella catarrhalis_** is another common causative agent of ASOM, responsible for 10-20% of cases. - It is frequently seen in conjunction with other pathogens but is not the most common on its own.

Q: What are the potential causes of myringosclerosis?

Chronic inflammation from recurrent infections. ***Chronic inflammation from recurrent infections*** - **Myringosclerosis** is often a consequence of **chronic inflammation** and repair processes in the tympanic membrane (eardrum), commonly triggered by **recurrent otitis media** (middle ear infections). - The inflammatory exudates and subsequent healing lead to the deposition of **calcium and phosphate crystals** within the fibrous layer of the tympanic membrane, causing it to become stiff and opaque. *Genetic predisposition* - While genetics can play a role in some ear conditions, **myringosclerosis** is primarily an **acquired condition** rather than one solely determined by genetic factors. - No specific strong genetic link has been identified as a primary cause compared to environmental triggers. *Otosclerosis* - **Otosclerosis** is a condition affecting the **ossicles** (typically the stapes) in the middle ear, leading to conductive hearing loss due to abnormal bone growth, not directly affecting the tympanic membrane. - Myringosclerosis involves the eardrum itself, characterized by **calcification of the tympanic membrane**, which is distinct from the pathology of otosclerosis. *None of the options* - This option is incorrect because **chronic inflammation from recurrent infections** is a well-established cause of myringosclerosis. - The presence of a correct answer negates this choice.

Q: What is the infective form of Trypanosoma brucei?

Trypomastigote. ***Trypomastigote*** - The **trypomastigote** is the infective form of *Trypanosoma brucei* transmitted to humans by the **tsetse fly** bite. - In the human host, trypomastigotes multiply in the **blood and lymphatic system**, eventually invading the central nervous system. *Amastigote form* - The **amastigote** form is characteristic of *Trypanosoma cruzi* and *Leishmania* species, not *Trypanosoma brucei*. - **Amastigotes** are found intracellularly and lack a flagellum, responsible for replication within host cells for these other parasites. *Egg stage* - *Trypanosoma brucei* is a **protozoan parasite** and does not have an **egg stage** in its life cycle. - Egg stages are typical for helminths, such as **tapeworms** or **flukes**. *No infective form* - This statement is incorrect; **all parasitic organisms** must have an infective stage to be transmitted to their hosts. - The **trypomastigote** is specifically adapted for transmission and survival in the human host and vector.

Q: Cutaneous larva migrans is due to ?

Ancylostoma braziliense. ***Ancylostoma braziliense*** - **Cutaneous larva migrans** is primarily caused by the larvae of **dog and cat hookworms**, especially *Ancylostoma braziliense*. - Humans become **accidental hosts** when these larvae penetrate the skin but cannot complete their life cycle, leading to **serpiginous tracks**. *W. bancrofti* - This parasite, **Wuchereria bancrofti**, is a filarial nematode that causes **lymphatic filariasis** (elephantiasis). - Its effects are characterized by **lymphedema** and **hydrocele**, not migrating skin lesions. *B. Malayi* - **Brugia malayi** is another filarial nematode responsible for **lymphatic filariasis** in humans, similar to *W. bancrofti*. - It primarily causes **swelling of the limbs** and scrotum, not cutaneous larva migrans. *D. medinensis* - **Dracunculus medinensis** is the parasite that causes **dracunculiasis**, also known as **Guinea worm disease**. - This infection is characterized by a **painful blister** and subsequent emergence of the adult worm, which is distinct from creeping eruptions.

Q: Which Schistosoma species is primarily associated with eggs being discharged in urine?

S. haematobium. ***S. haematobium*** - *S. haematobium* specifically targets the **urinary bladder plexus**, leading to the discharge of eggs in the **urine**. - Infection with *S. haematobium* is the primary cause of **urinary schistosomiasis** and is associated with complications like **hematuria** and bladder cancer. *S. japonicum (intestinal)* - *S. japonicum* primarily infects the **mesenteric veins of the small intestine** and discharges its eggs in **feces**, not urine. - This species is known for causing severe **intestinal and hepatic schistosomiasis** due to the large number of eggs produced. *S. mansoni (intestinal)* - *S. mansoni* also primarily infects the **mesenteric veins, mainly of the large intestine**, and its eggs are excreted in **feces**. - It is a common cause of **intestinal schistosomiasis**, leading to symptoms such as abdominal pain, diarrhea, and hepatosplenomegaly. *S. mekongi* - *S. mekongi* is another **intestinal schistosome**, closely related to *S. japonicum*, and its eggs are discharged in **feces**. - This species is found in specific regions of Southeast Asia and causes similar symptoms to other intestinal schistosomes.

Q: In malaria, pre-erythrocytic schizogony occurs in -

Liver. ***Liver*** - After being introduced by a mosquito bite, **Plasmodium sporozoites** rapidly travel to the liver - In the liver, they invade **hepatocytes** and undergo asexual reproduction, known as **pre-erythrocytic (or hepatic) schizogony**, forming merozoites - This is the exo-erythrocytic cycle that occurs before red blood cell invasion *Lung* - The lungs are not a primary site for **Plasmodium** development or asexual reproduction in the human host - While some parasite components or host immune responses might involve the lungs in severe malaria, it is not where pre-erythrocytic schizogony occurs *Spleen* - The **spleen** is primarily involved in clearing infected red blood cells and acts as a site for immune responses to malaria, but not for initial schizogony - It plays a significant role in the **erythrocytic stage** of malaria by filtering and destroying parasitized red blood cells *Kidney* - The **kidneys** are not involved in the life cycle of the **Plasmodium parasite** during pre-erythrocytic schizogony - While malaria can cause **renal complications** (such as acute kidney injury in severe cases), this is a pathological effect, not a site of parasite development

Q: Trophozoites in stool are characteristically seen in which of the following conditions?

**Note:** This question has significant issues. Trophozoites in stool are characteristically seen in **protozoal infections** such as *Entamoeba histolytica* (amoebiasis), *Giardia lamblia*, or *Balantidium coli* [1][2] - none of which are listed as options. ***None of the given options is medically accurate*** for characteristic trophozoites in stool. However, if forced to choose from these options: *Ascariasis* - **Ascariasis** is caused by the nematode *Ascaris lumbricoides* - Diagnosis is by identifying **ova (eggs)** in stool, not trophozoites - Trophozoites are protozoal forms, not associated with helminthic infections [2] *Strongyloidiasis* - Caused by *Strongyloides stercoralis* (nematode) - Typically diagnosed by finding **rhabditiform or filariform larvae** in stool - Not characterized by trophozoites in routine stool examination *Eosinophilic gastroenteritis* - Inflammatory condition with **eosinophilic infiltration** of GI tract - Not a parasitic infection - No trophozoites present - diagnosis is by endoscopic biopsy showing eosinophils *Allergic colitis* - Inflammatory condition related to **food allergies** (common in infants) - Presents with blood and mucus in stool with eosinophilia - Not an infectious process - no trophozoites present **Clinical Pearl:** Trophozoites (motile feeding stage of protozoa) in stool are diagnostic of **acute intestinal protozoal infections** like amoebiasis or giardiasis, where they must be identified in fresh, warm stool samples as they rapidly deteriorate [1][2]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Alimentary System Disease, pp. 364-365. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, pp. 801-802.

Question 1

Most common mode of transmission of nosocomial infection is -

Accepted Answer

Hand contact

Answer

Droplet infection

Answer

Blood and blood products

Answer

Contaminated water

Question 2

The BEINGS Model of disease causation does not include which of the following factors?

Accepted Answer

Spiritual factors

Answer

Religious factors

Answer

Social factors

Answer

Nutritional factors

Question 3

Which of the following viral diseases is least commonly reported in India?

Accepted Answer

Lassa fever

Answer

Japanese B encephalitis

Answer

KFD

Answer

Dengue

Question 4

What is the most common cause of ASOM?

Accepted Answer

Pneumococci

Answer

Meningococci

Answer

H. influenzae

Answer

Moraxella catarrhalis

Question 5

What are the potential causes of myringosclerosis?

Accepted Answer

Chronic inflammation from recurrent infections

Answer

Genetic predisposition

Answer

Otosclerosis

Answer

None of the options

Question 6

What is the infective form of Trypanosoma brucei?

Accepted Answer

Trypomastigote

Answer

Amastigote form

Answer

Egg stage

Answer

No infective form

Question 7

Cutaneous larva migrans is due to ?

Accepted Answer

Ancylostoma braziliense

Answer

W.bancrofti

Answer

B. Malayi

Answer

D. medinensis

Question 8

Which Schistosoma species is primarily associated with eggs being discharged in urine?

Accepted Answer

S. haematobium

Answer

S. japonicum

Answer

S. mansoni

Answer

S. mekongi

Question 9

In malaria, pre-erythrocytic schizogony occurs in -

Accepted Answer

Liver

Answer

Lung

Answer

Spleen

Answer

Kidney

Question 10

Trophozoites in stool are characteristically seen in which of the following conditions?

Answer

Ascariasis

Answer

Strongyloidiasis

Answer

Allergic colitis

Answer

Eosinophilic gastroenteritis

NEET-PG 2013

Community Medicine

ENT

Microbiology

Pathology