Infectious Diseases Practice Questions

Q: A 12-year-old child presents with fever, sore throat for 3 days and posterior cervical lymphadenopathy. Peripheral smear was performed. Diagnosis is?

Infectious mononucleosis. ***Infectious mononucleosis*** - The image shows an **atypical lymphocyte** (Downey cell), characterized by a large, irregularly shaped nucleus and abundant, basophilic cytoplasm, often indenting surrounding red blood cells. These are characteristic of infectious mononucleosis. - The clinical presentation of **fever**, **sore throat**, and **posterior cervical lymphadenopathy** in a 12-year-old child is typical for infectious mononucleosis, commonly caused by the **Epstein-Barr virus (EBV)**. *Hodgkin lymphoma* - While Hodgkin lymphoma presents with lymphadenopathy, it typically involves **Reed-Sternberg cells** on biopsy, which are not seen in a peripheral smear. - Furthermore, the clinical course and presentation of Hodgkin lymphoma are usually more chronic and would not typically present with the acute viral-like syndrome described. *CLL* - **Chronic Lymphocytic Leukemia (CLL)** is a malignancy of mature B lymphocytes, primarily affecting older adults, and would be rare in a 12-year-old. - Peripheral smears in CLL show mature-appearing lymphocytes, often with "smudge cells," which are distinct from the atypical lymphocytes seen in the image. *Herpangina* - Herpangina is a viral illness causing **fever** and **painful mouth sores** (vesicles and ulcers) in the posterior oropharynx, often caused by Coxsackievirus. - While it can cause fever and sore throat, it does not typically present with significant lymphadenopathy, especially **posterior cervical lymphadenopathy**, and would not show atypical lymphocytes on a peripheral smear.

Q: A child is brought to your OPD with rashes as shown below along with fever. Diagnosis is:

Meningococcemia. ***Meningococcemia*** - The image shows a **purpuric rash** with some confluent lesions, which are highly characteristic of **meningococcemia**, especially in a child with fever. - This rash is caused by **endotoxin-mediated vascular damage**, leading to petechiae and purpura that do not blanch under pressure. *Dengue haemorrhagic fever* - While dengue can cause petechiae and purpuric rashes, it typically presents with a more generalized rash, bleeding manifestations like **epistaxis** or **gum bleeding**, and often a history of mosquito exposure. - The rash in dengue is often described as an **"islands of white in a sea of red"** pattern, which is distinct from the more widespread, darker purpuric lesions seen in the image. *Leptospirosis* - Leptospirosis can manifest with a rash, but it is typically **maculopapular** or **erythematous**, sometimes appearing petechial. However, it rarely presents with the extensive, dark purpuric lesions shown, which are indicative of widespread microvascular damage. - Other classic features include **conjunctival suffusion**, myalgia, and severe headache, often following exposure to contaminated water or animal urine. *Scrub typhus* - Scrub typhus typically presents with a **maculopapular rash** that may become generalized, often sparing the face, palms, and soles. A characteristic **eschar** at the site of the chigger bite is a key diagnostic feature. - While petechiae can occur, the widespread, dark purpuric lesions seen in the image are not typical for scrub typhus.

Q: Which of the following statements are correct regarding vaccination routes for children? I. Hepatitis B vaccine given in deltoid region has reduced efficacy II. Two vaccines may be given in the same thigh, but separated by 1 inch III. Separate sites are used when administering a vaccine and an immunoglobulin IV. Two intramuscular vaccines should never be given on the same day Select the answer using the code given below:

II and III. ***II and III*** - Hepatitis B vaccine can be given in the **deltoid region** for older children and adults with good efficacy; reduced efficacy primarily occurs if administered in the gluteal region due to high fat content, not the deltoid. Administering two vaccines in the same thigh, separated by 1 inch, is a recognized practice when multiple injections are needed and separate limbs are not feasible. - Administering a vaccine and an immunoglobulin at **separate sites** is crucial to prevent the immunoglobulin from neutralizing the live attenuated vaccine, thereby reducing its efficacy. *I and III* - Statement I is incorrect because the **deltoid region** is an appropriate and effective site for Hepatitis B vaccine administration in older children and adults. - Statement III is correct, as separating the sites for vaccine and immunoglobulin prevents **immune interference**. *III only* - While statement III is correct regarding the separation of vaccine and immunoglobulin administration, statement II is also correct, making this option incomplete. - **Multiple injections** on the same limb with adequate spacing are acceptable under certain guidelines. *II, III, and IV* - Statement IV is incorrect; multiple **intramuscular vaccines** *can* be given on the same day if clinically indicated and the child is due for them, often in different limbs or at appropriately spaced sites on the same limb. - Statements II and III are correct, but the inclusion of the incorrect statement IV makes this option invalid.

Q: In a child aged 3-12 years with an ear problem, which one of these situations merits urgent referral to hospital?

Tender swelling behind the ear. ***Tender swelling behind the ear*** - A **tender swelling behind the ear**, particularly in a child with an ear problem, is a classic sign of **mastoiditis**, which is a serious complication requiring urgent medical attention due to the risk of intracranial spread. - **Mastoiditis** often presents with fever, pain, and a prominent, pushed-out auricle. *Pus seen draining from the ear, and discharge reported for more than or equal to 14 days* - This suggests **chronic suppurative otitis media (CSOM)**, which typically requires a referral to ENT for assessment and management but is not usually an *urgent* referral unless there are signs of complications. - While concerning, the chronicity itself doesn't immediately indicate an acute emergency in the absence of other symptoms like fever or severe pain. *Pus seen draining from the ear, and discharge reported for less than 14 days* - This indicates acute otitis media (AOM) with perforation, which is very common in children. - It usually resolves with antibiotics and local care, and while a follow-up is important, it doesn't typically require urgent hospital referral. *Pus seen draining from both ears, irrespective of duration* - Bilateral ear discharge suggests bilateral acute or chronic otitis media, but does not inherently imply an acute emergency that requires urgent hospital referral. - The key factor for urgency would be signs of complications, such as mastoiditis or intracranial involvement, rather than the bilaterality of discharge alone.

Q: Which of the following statements are correct about oral rotavirus vaccines? I. The storage should be at 2-8°C II. The vaccine should be used within 2 hours of reconstitution or opening III. Past history of intussusception is a contraindication IV. The vaccine can be given if the baby has ongoing diarrhoea Select the answer using the code given below :

I and III. ***I and III*** * **Oral rotavirus vaccines** require storage at **2-8°C** to maintain potency (cold chain maintenance is essential). * A past history of **intussusception** is an **absolute contraindication** due to increased risk of recurrence. *I and II* * While statement I is correct, statement II is incorrect because oral rotavirus vaccines (Rotarix, RotaTeq) are **ready-to-use liquid formulations** that do **not require reconstitution**. Once the container is opened, the vaccine should be **administered immediately** during the same vaccination visit, not stored for 2 hours. *II and IV* * Statement II is incorrect as oral rotavirus vaccines are **ready-to-use** and should be **administered immediately** after opening, without any reconstitution. * Statement IV is incorrect because the vaccine **should be postponed** if the baby has ongoing **moderate to severe diarrhoea** or vomiting, as this may affect vaccine absorption and effectiveness. Mild diarrhea is not a contraindication, but significant gastroenteritis warrants deferral. *III and IV* * While statement III is correct, statement IV is incorrect because ongoing **moderate to severe diarrhoea** is a reason to **postpone** administration of the rotavirus vaccine until the child recovers.

Q: All cases of severe measles and all cases of measles in areas with high case fatality rate need to be treated with which of the following vitamins?

Vitamin A. ***Vitamin A*** - **Vitamin A supplementation** is recommended for severe measles cases, especially in areas with high case fatality rates. - It helps to reduce morbidity and mortality by improving immune function and supporting the integrity of epithelial tissues. *Vitamin K* - **Vitamin K** is primarily involved in **blood clotting** and bone metabolism. - There is no established role for Vitamin K supplementation in the treatment or prognosis of measles. *Vitamin C* - **Vitamin C** is an **antioxidant** and supports immune function, but its role in measles management is not supported by strong evidence or recommendations. - While beneficial for overall immunity, it is not specifically indicated for severe measles as a life-saving intervention. *Vitamin D* - **Vitamin D** plays a crucial role in **bone health** and modulating the immune system. - Like Vitamin C, it has general immune benefits but is not a specific or recommended treatment for severe measles or its complications.

Q: In measles, when do the Koplik's spots appear?

1-2 days before the rashes appear. ***1-2 days before the rashes appear*** - **Koplik's spots** are considered an **enanthem**, a pathognomonic sign of **measles**. - These small, white spots with a bluish-white center on an erythematous base on the buccal mucosa typically appear 1-2 days before the generalized maculopapular rash. *On the day that rashes appear* - The generalized **maculopapular rash** of measles typically appears a few days *after* Koplik's spots. - While the rash is a hallmark of measles, it is preceded by the oral lesions. *On the day that fever occurs* - **Fever** is usually one of the initial symptoms of measles, often appearing several days before Koplik's spots. - The fever is part of the **prodromal phase**, which includes cough, coryza, and conjunctivitis. *1-2 days before the fever occurs* - Measles symptoms, including fever, are usually the first indicators of infection, making it unlikely for a specific sign like Koplik's spots to appear before the fever itself. - The incubation period precedes any symptoms, including fever.

Q: Varicella-Zoster Immunoglobulin (VZIG) is NOT recommended for which of the exposed susceptible individuals?

Healthy sibling. ***Correct: Healthy sibling*** - VZIG is administered to **susceptible individuals** upon exposure to **Varicella-Zoster Virus (VZV)** to prevent or attenuate the infection - A **healthy sibling** with a **competent immune system** would typically mount an adequate immune response to the virus - VZIG is therefore **NOT indicated** for immunocompetent individuals as they can handle the infection naturally - VZIG is reserved for **high-risk populations** where varicella could cause severe complications *Incorrect: HIV/AIDS positive* - Individuals with **HIV/AIDS** are considered **immunocompromised** and are at **higher risk** for severe varicella infection and complications - VZIG **IS recommended** for these patients after exposure to VZV to provide **passive immunity** and reduce disease severity - This is particularly important in patients with CD4 counts <200 cells/μL *Incorrect: Newborn* - **Newborns** whose mothers developed varicella **5 days before to 2 days after delivery** are at high risk for severe, disseminated neonatal varicella - **VZIG IS recommended** for these neonates to offer immediate protection against the virus - Also indicated for premature infants <28 weeks or <1000g who are exposed, regardless of maternal immunity *Incorrect: Pregnant women* - **Pregnant women** who are **non-immune to varicella** and exposed to VZV are at risk for both **maternal complications** (varicella pneumonia) and **fetal abnormalities** (congenital varicella syndrome) - **VZIG IS recommended** for susceptible pregnant women exposed to varicella to reduce the risk of severe maternal disease - Should be administered within **10 days** of exposure, preferably within 96 hours

Q: The classical triad of congenital defects in Congenital Rubella Syndrome include which of the following? 1. Hydrocephalus 2. Deafness 3. Cardiac malformations 4. Cataract

2, 3 and 4. ***2, 3 and 4*** - The classical triad of congenital defects associated with **Congenital Rubella Syndrome (CRS)** typically refers to **deafness**, **cataracts**, and **cardiac malformations**. - These are the most common and prominent features that result from transplacental infection during early pregnancy. *1, 2 and 3 and 4* - This option incorrectly includes **hydrocephalus** as part of the classical triad. While other neurological manifestations can occur in CRS, hydrocephalus is not a defining feature of the classical triad. - The three most prominent and characteristic defects in CRS are **deafness, cataracts, and cardiac malformations**. *1, 2 and 4* - This option incorrectly includes **hydrocephalus** and omits **cardiac malformations**, which is a key component of the classical triad. - The classical triad specifically highlights defects in the **eyes (cataracts)**, **ears (deafness)**, and **heart (cardiac malformations)**. *1, 2 and 3* - This option incorrectly includes **hydrocephalus** and omits **cataracts**, which is a definitive feature of the classical triad of CRS. - While cardiac and auditory defects (deafness) are part of the triad, ocular defects (cataracts) are equally crucial for the classical definition.

Q: Which of the following are the features of Rubella? 1. Rashes appear within 24 hours of onset of symptoms 2. Incubation period is 2 – 3 weeks 3. False membrane is formed in throat 4. Post auricular lymph nodes enlarge Select the correct answer using the code given below:

2 and 4 only. ***Correct: 2 and 4 only*** - **Incubation period of 2-3 weeks** is accurate for rubella (14-21 days) - **Postauricular lymphadenopathy** along with suboccipital and posterior cervical lymph node enlargement are **classic hallmark features** of rubella, often appearing before the rash - These two features correctly identify rubella infection *Incorrect: 1, 2 and 4* - While statements 2 and 4 are correct, **statement 1 is medically inaccurate** - The rubella rash does NOT appear within 24 hours of symptom onset - Rubella typically has a **prodromal period of 1-5 days** with low-grade fever and malaise before the rash appears - The rash spreads from face to trunk within 24 hours, but this is different from appearing within 24 hours of initial symptoms *Incorrect: 2 and 3 only* - While the incubation period (statement 2) is correct, **false membrane formation in the throat** is characteristic of **diphtheria**, not rubella - Rubella does not cause pseudomembranous pharyngitis - This option also omits the classic postauricular lymphadenopathy *Incorrect: 1, 2 and 3* - Statement 1 is inaccurate regarding rash timing - Statement 3 describes diphtheria, not rubella - Only statement 2 (incubation period) is correct in this combination

Question 1

A 12-year-old child presents with fever, sore throat for 3 days and posterior cervical lymphadenopathy. Peripheral smear was performed. Diagnosis is?

Accepted Answer

Infectious mononucleosis

Answer

Hodgkin lymphoma

Answer

CLL

Answer

Herpangina

Question 2

A child is brought to your OPD with rashes as shown below along with fever. Diagnosis is:

Accepted Answer

Meningococcemia

Answer

Dengue haemorrhagic fever

Answer

Leptospirosis

Answer

Scrub typhus

Question 3

Which of the following statements are correct regarding vaccination routes for children?
I. Hepatitis B vaccine given in deltoid region has reduced efficacy
II. Two vaccines may be given in the same thigh, but separated by 1 inch
III. Separate sites are used when administering a vaccine and an immunoglobulin
IV. Two intramuscular vaccines should never be given on the same day

Select the answer using the code given below:

Accepted Answer

II and III

Answer

I and III

Answer

III only

Answer

II, III, and IV

Question 4

In a child aged 3-12 years with an ear problem, which one of these situations merits urgent referral to hospital?

Accepted Answer

Tender swelling behind the ear

Answer

Pus seen draining from the ear, and discharge reported for more than or equal to 14 days

Answer

Pus seen draining from the ear, and discharge reported for less than 14 days

Answer

Pus seen draining from both ears, irrespective of duration

Question 5

Which of the following statements are correct about oral rotavirus vaccines?
I. The storage should be at 2-8°C
II. The vaccine should be used within 2 hours of reconstitution or opening
III. Past history of intussusception is a contraindication
IV. The vaccine can be given if the baby has ongoing diarrhoea

Select the answer using the code given below :

Accepted Answer

I and III

Answer

I and II

Answer

II and IV

Answer

III and IV

Question 6

All cases of severe measles and all cases of measles in areas with high case fatality rate need to be treated with which of the following vitamins?

Accepted Answer

Vitamin A

Answer

Vitamin K

Answer

Vitamin C

Answer

Vitamin D

Question 7

In measles, when do the Koplik's spots appear?

Accepted Answer

1-2 days before the rashes appear

Answer

On the day that rashes appear

Answer

On the day that fever occurs

Answer

1-2 days before the fever occurs

Question 8

Varicella-Zoster Immunoglobulin (VZIG) is NOT recommended for which of the exposed susceptible individuals?

Accepted Answer

Healthy sibling

Answer

HIV/AIDS positive

Answer

Newborn

Answer

Pregnant women

Question 9

The classical triad of congenital defects in Congenital Rubella Syndrome include which of the following?

1. Hydrocephalus
2. Deafness
3. Cardiac malformations
4. Cataract

Accepted Answer

2, 3 and 4

Answer

1, 2 and 3 and 4

Answer

1, 2 and 4

Answer

1, 2 and 3

Question 10

Which of the following are the features of Rubella?

1. Rashes appear within 24 hours of onset of symptoms
2. Incubation period is 2 – 3 weeks
3. False membrane is formed in throat
4. Post auricular lymph nodes enlarge

Select the correct answer using the code given below:

Accepted Answer

2 and 4 only

Answer

2 and 3 only

Answer

1, 2 and 4

Answer

1, 2 and 3

Infectious Diseases — MCQs

Infectious Diseases — MCQs

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