INI-CET 2018 Practice Questions

Q: Which is incorrect about the image shown below?

75 % values are above 25 mg. ***75 % values are above 25 mg*** - This statement is incorrect. In a box plot, the **second quartile (Q2)** or **median** represents the 50th percentile. The upper boundary of the lower box (Q2) is at 23 mg, meaning 50% of values are above 23 mg. - The upper boundary of the upper box (Q3) is at 35 mg, meaning 25% of values are above 35 mg. Therefore, it is incorrect to say 75% of values are above 25 mg. *Negatively skewed* - The long **tail of the distribution** is on the left side, as indicated by the lower whisker extending further from the box than the upper whisker, and the lower half of the box being larger than the upper half. - In a negatively skewed distribution, the **mean is typically less than the median**, and the bulk of the values are concentrated on the higher end. *Positively skewed* - This statement is incorrect. A **positively skewed** distribution would have a longer tail on the right side, meaning the upper whisker would be longer than the lower whisker and the upper box larger than the lower box. - The provided image shows the opposite, with the longer tail towards the lower values. *Median is 50 mg* - The **median** is represented by the line dividing the lower and upper halves of the box. In this box plot, the median line is at approximately **23 mg**, not 50 mg. - The box itself represents the **interquartile range (IQR)**, with the median dividing it.

Q: Which of the following is true about the box plot shown?

Mean = median, not equal to mode. ***Mean = median, not equal to mode*** - A **perfectly symmetrical distribution** (represented by a **symmetrical box plot without whiskers extending further in one direction**) indicates that the **mean and median are equal**. - However, the mode, which is the most frequent value, is not necessarily equal to the mean and median in all symmetrical distributions, especially if it's **not unimodal or not centered at the mean/median**. When depicted using a boxplot, we cannot ascertain the mode simply by looking at where the median lies. *Mean = median = mode* - While the **mean and median are equal** in a symmetrical distribution, the **mode is not explicitly represented** in a box plot. - The mode is the most frequently occurring value, and a box plot primarily shows quartiles and spread, not individual frequencies. *Mean = mode, not equal to median* - In a symmetrical distribution, the **mean and median are equal**. - Therefore, this option is incorrect as it states the mean is not equal to the median. *Mean, median and mode are not equal* - The **symmetrical nature** of the box plot strongly suggests that the **mean and median are equal**. - This option is therefore incorrect, as at least two of the measures of central tendency are equal.

Q: Post kidney transplantation, a patient presents with diarrhoea. The motility of the worms is shown in the figure. Correct statement about the organism is: (AIIMS Nov 2018)

Loeffler pneumonia is caused by the same organism. ***Loeffler pneumonia is caused by the same organism*** - The image shows **Strongyloides stercoralis larvae** with characteristic motility. In a post-kidney transplant patient with diarrhea, this points to **Strongyloides hyperinfection** due to immunosuppression. - **Loeffler's syndrome (Loeffler pneumonia)** is a transient pulmonary infiltrative disease with eosinophilia, caused by larval migration through lungs. It is classically associated with *Strongyloides stercoralis*, *Ascaris lumbricoides*, and hookworms during their migratory phase. - This option represents an important **clinical association** that connects the organism to a significant pulmonary manifestation. *Monoecious organism related with parthenogenesis* - *Strongyloides stercoralis* is **dioecious (unisexual)**, not monoecious, meaning it has separate male and female forms. - While the parasitic females do exhibit **parthenogenesis** (reproducing without fertilization), the organism is not monoecious. *Transmitted by intake of contaminated food and water* - This is **incorrect**. *Strongyloides stercoralis* is transmitted through **percutaneous penetration** by filariform larvae from contaminated soil. - Fecal-oral transmission via contaminated food/water applies to parasites like *Entamoeba histolytica*, *Giardia*, *Ascaris*, and *Enterobius*, but not *Strongyloides*. *Infection occurs by filariform larvae* - This statement is **factually correct** - infection with *Strongyloides* does occur through **filariform (L3) larvae** penetrating intact skin. - However, in the context of this PYQ, Option C is preferred as it highlights the **clinically significant pulmonary manifestation** (Loeffler's syndrome) that is particularly relevant in immunocompromised patients, while this option merely describes the mode of transmission without clinical correlation.

Q: The technique shown in the picture is used for: (AIIMS Nov 2018)

Synthesis of monoclonal antibodies. ***Synthesis of monoclonal antibodies*** - The image depicts the process of creating **hybridomas** by fusing antibody-producing spleen cells from an immunized mouse with myeloma cells. - These hybridomas are then cultured in **HAT medium** to select for stable cell lines that continuously produce a single type of antibody, known as **monoclonal antibodies**. *Preparing cell lines for viral culture* - While cell cultures are used for viral studies, the specific methodology shown involving immunization, spleen cell extraction, and fusion with myeloma cells is not for preparing routine **viral cultures**. - Viral culture typically involves growing target cells that are susceptible to a virus and then inoculating them with the virus for replication and study. *Synthesis of vaccine* - **Vaccine synthesis** involves producing antigens (e.g., inactivated viruses, attenuated microbes, or recombinant proteins) to stimulate an immune response, not the production of antibodies themselves. - The process shown aims to generate antibodies, which could *potentially* be used therapeutically, but not primarily for vaccine production. *Process of genetic engineering* - **Genetic engineering** involves manipulating an organism's genes, such as introducing foreign DNA or modifying existing genes. - While molecular biology techniques are involved in antibody production, the core process of fusing cells to create hybridomas specifically for large-scale antibody production is distinct from typical genetic engineering methods like gene cloning or gene editing.

Q: The life cycle shown below is of:

Nipah virus. ***Nipah virus*** - The diagram clearly illustrates the transmission pathways characteristic of Nipah virus, involving **fruit bats (flying foxes)** as primary reservoirs, **pigs as intermediate hosts**, and human infection through direct contact with infected animals or consumption of **contaminated date palm sap**. - The described "rapid pig-to-pig transmission" and "people consume contaminated date palm sap" are key epidemiological features of Nipah virus outbreaks in Southeast Asia. *Japanese encephalitis* - Japanese encephalitis is primarily transmitted by **mosquitoes** (Culex species) and involves **water birds** as primary reservoirs, and pigs as amplifying hosts. - The life cycle shown does not depict mosquito vectors or water birds, which are central to Japanese encephalitis transmission. *Chandipura virus* - Chandipura virus is an arbovirus transmitted by **sandflies** and often associated with seasonal outbreaks of acute encephalitis, primarily affecting children. - Its transmission cycle does not involve bats, pigs, or contaminated date palm sap as depicted in the image. *Influenza* - Influenza viruses circulate mainly among **humans, birds, and pigs**, with transmission primarily through **respiratory droplets** or direct contact. - While pigs can play a role in certain influenza strains (e.g., swine flu), the involvement of bats and consumption of contaminated sap is not characteristic of human influenza transmission.

Q: A 10-year-old child presents with fever and wound with discharging pus from right thigh for 4 months. Given below is the X -ray of the patient. Identify the marked area:

Sequestrum. ***Sequestrum*** - The arrow points to a dense, isolated fragment of **necrotic bone** within the bone shaft, which is a classic radiographic finding of a **sequestrum** in chronic osteomyelitis. - In chronic osteomyelitis, the host immune system attempts to wall off the infection, leading to bone necrosis and the formation of this devitalized bone fragment. *Cloacae* - A cloaca is an opening or channel in the **involucrum** (new bone formation) through which pus and necrotic debris (sequestrum) can drain from the infected bone. - The image does not clearly show an opening for drainage; rather, it highlights an internal bone fragment. *Involucrum* - The involucrum is a sheath of **new bone formation** that encapsulates the infected, necrotic bone (sequestrum) in chronic osteomyelitis. - While new bone formation is likely present, the arrow specifically indicates the denser, dead bone fragment rather than the surrounding reactive new bone. *Woven bone* - **Woven bone** is immature, rapidly formed bone, often seen during bone development, fracture healing, or in certain pathological conditions like fibrous dysplasia or Paget's disease. - The marked area is a distinct fragment of necrotic cortical bone, not indicative of diffuse woven bone formation.

Q: Given is the X-ray of a 7-year-old child. Identify the deformity:

Perthe's disease. ***Perthe's disease*** - The X-ray shows changes consistent with **Perthe's disease**, characterized by **avascular necrosis of the femoral head**. Findings include **flattening of the femoral head**, **sclerosis**, and potential **fragmentation**. - This condition typically affects *children between 4 and 10 years old*, matching the age of the child in the question (7 years old). *Coxa vara* - **Coxa vara** is defined by a **decreased femoral neck-shaft angle** (less than 120 degrees), leading to a more horizontal orientation of the femoral neck. - While *Perthe's disease can lead to coxa vara* as a complication, the primary pathological changes (sclerosis, flattening, fragmentation of the femoral head) are distinctive of Perthe's. *Coxa valga* - **Coxa valga** is characterized by an **increased femoral neck-shaft angle** (greater than 135-140 degrees), causing the femoral neck to be more vertical. - This is the opposite of coxa vara and is not typically associated with the radiographic findings observed in the image. *Brodie's abscess* - A **Brodie's abscess** is a **subacute or chronic osteomyelitis**, often appearing as a **well-circumscribed luncency** with a sclerotic rim, commonly found in the metaphysis of long bones. - The X-ray does not show a focal lytic lesion suggestive of an abscess; instead, it presents diffuse changes to the femoral epiphysis.

Q: Identify the lesion in the X-ray shown below:

Aneurysmal bone cyst. ***Aneurysmal bone cyst*** - The image shows a **lytic, expansile lesion** in the distal radius with a **"soap bubble" appearance**, characteristic of an aneurysmal bone cyst. - These are typically **benign, blood-filled lesions** that cause bone remodeling and expansion. *Giant cell tumour* - While also a **lytic lesion**, giant cell tumors are usually more aggressive and often show **cortical destruction** and less distinct margins without the typical septations seen here. - They tend to occur in the **epiphysis** of long bones after epiphyseal closure. *Osteoma* - An osteoma is a **benign, dense, sclerotic bone growth**, appearing as a very bright, compact lesion on X-ray, which is clearly not depicted in the image. - These are typically **asymptomatic** and found incidentally. *Osteosarcoma* - This is a **highly malignant primary bone tumor** that typically presents with a **blastic or mixed lytic-blastic appearance**, often with a **"sunburst" pattern** or **Codman's triangle**, characteristics not seen in this image. - It usually causes significant **cortical destruction** and a more aggressive soft tissue mass.

Q: Identify the lesion in a 20-year-old male whose foot X-ray is shown below:

Mycetoma. ***Mycetoma*** - The X-ray image shows a **lytic lesion** with surrounding sclerosis in the calcaneus, indicated by the arrow, which is characteristic of **mycetoma**. The histological image reveals an inflammatory infiltrate with **pigmented fungal grains (brown aggregates)**, confirming the diagnosis. - Mycetoma is a chronic granulomatous infection of subcutaneous tissues, often extending to bone, particularly in the foot. Its characteristic features include **grains (colonies of microorganisms)** within the lesions. *Ochronosis* - Ochronosis would show **dark discoloration of cartilage** and connective tissues due to **homogentisic acid** deposition, leading to degenerative arthritis. This would appear on X-ray as **calcification of cartilage** (e.g., intervertebral discs, menisci) rather than focal lytic lesions with grains. - The histological image would show characteristic **ochre-colored pigment deposits**, not fungal grains. *Haemophilic pseudo-tumour* - A haemophilic pseudo-tumour is a rare complication of hemophilia, often presenting as a **large, expanding lesion** within bone or soft tissue, typically due to recurrent hemorrhage. - X-rays would reveal a **well-defined, expansile lesion** with cortical thinning or bone destruction, and histology would show features of chronic hemorrhage, fibrous tissue, and hemosiderin deposition, not fungal grains. *Pigmented villonodular synovitis* - This condition involves **proliferation of synovial tissue**, often affecting large joints like the knee or hip, leading to bone erosions and cysts. - Histology would show **hyperplastic synovium** with hemosiderin deposition, multinucleated giant cells, and lipid-laden macrophages, but not fungal grains as seen in the microscopy image.

Q: Comment on the test being performed in the patient.

Hoover sign. ***Hoover sign*** - The image depicts the Hoover sign, which tests for **non-organic weakness** in a lower limb. - The examiner asks the patient to lift one leg while feeling for contralateral heel pressure; absence of pressure indicates an inconsistent effort. *McMurray* - The McMurray test evaluates for a **meniscal tear** in the knee. - It involves flexing and rotating the knee while extending it to elicit a click or pain. *Apley's grinding test* - Apley's grinding test is used to assess for **meniscal or ligamentous injury** in the knee. - The patient lies prone, and the examiner applies downward pressure with rotation to the flexed knee. *Gordon sign* - The Gordon sign is a pathological reflex used to identify **upper motor neuron lesions**. - It involves squeezing the calf muscle, which results in **dorsiflexion of the great toe** and fanning of the other toes, similar to a Babinski sign.

Question 1

Which is incorrect about the image shown below?

Accepted Answer

75 % values are above 25 mg

Answer

Negatively skewed

Answer

Positively skewed

Answer

Median is 50 mg

Question 2

Which of the following is true about the box plot shown?

Accepted Answer

Mean = median, not equal to mode

Answer

Mean = median = mode

Answer

Mean = mode, not equal to median

Answer

Mean, median and mode are not equal

Question 3

Post kidney transplantation, a patient presents with diarrhoea. The motility of the worms is shown in the figure. Correct statement about the organism is: (AIIMS Nov 2018)

Accepted Answer

Loeffler pneumonia is caused by the same organism

Answer

Monoecious organism related with parthenogenesis

Answer

Transmitted by intake of contaminated food and water

Answer

Infection occurs by filariform larvae

Question 4

The technique shown in the picture is used for: (AIIMS Nov 2018)

Accepted Answer

Synthesis of monoclonal antibodies

Answer

Preparing cell lines for viral culture

Answer

Synthesis of vaccine

Answer

Process of genetic engineering

Question 5

The life cycle shown below is of:

Accepted Answer

Nipah virus

Answer

Japanese encephalitis

Answer

Chandipura virus

Answer

Influenza

Question 6

A 10-year-old child presents with fever and wound with discharging pus from right thigh for 4 months. Given below is the X -ray of the patient. Identify the marked area:

Accepted Answer

Sequestrum

Answer

Cloacae

Answer

Involucrum

Answer

Woven bone

Question 7

Given is the X-ray of a 7-year-old child. Identify the deformity:

Accepted Answer

Perthe's disease

Answer

Coxa vara

Answer

Coxa valga

Answer

Brodie's abscess

Question 8

Identify the lesion in the X-ray shown below:

Accepted Answer

Aneurysmal bone cyst

Answer

Giant cell tumour

Answer

Osteoma

Answer

Osteosarcoma

Question 9

Identify the lesion in a 20-year-old male whose foot X-ray is shown below:

Accepted Answer

Mycetoma

Answer

Ochronosis

Answer

Haemophilic pseudo-tumour

Answer

Pigmented villonodular synovitis

Question 10

Comment on the test being performed in the patient.

Accepted Answer

Hoover sign

Answer

McMurray

Answer

Apley's grinding test

Answer

Gordon sign

INI-CET 2018

Community Medicine

Microbiology

Orthopaedics

Pathology

Psychiatry