Koplik spot is the typical sign of?

Appeared in: NHM MP Staff Nurse - 2015

Explanation

Koplik spots are the pathognomonic sign of measles (rubeola), meaning their presence confirms the diagnosis.
These spots appear as small, bluish-white dots on a red base, famously described as 'grains of salt on a red background'.
They are located on the buccal mucosa (inner cheek), usually opposite the lower molars.
Crucially, they are an early sign, appearing 1-4 days before the characteristic maculopapular rash, allowing for early diagnosis and isolation.

Option A: Mumps is incorrect. The hallmark sign of mumps is parotitis, the painful swelling of the salivary glands located below and in front of the ears.
Option C: Pertussis is incorrect. The characteristic sign of pertussis is a severe, paroxysmal cough followed by a high-pitched inspiratory 'whoop', which gives the disease its common name, 'whooping cough'.
Option D: Diphtheria is incorrect. The classic sign of diphtheria is the formation of a thick, gray, adherent pseudomembrane on the tonsils and pharynx, which can lead to airway obstruction and a 'bull neck' appearance.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Pathognomonic signs of childhood infectious diseases as background academic context rather than a clinical decision trigger.
Early identification of Koplik spots is a critical nursing responsibility as it allows for the diagnosis of measles before the contagious rash appears.
Prompt recognition enables the immediate implementation of airborne precautions (e.g., patient isolation in a negative pressure room, use of N95 respirators by staff) to prevent nosocomial outbreaks.
What if? If a child presents with fever and a rash but a thorough oral examination reveals no Koplik spots, the nurse should consider other differential diagnoses like rubella, roseola, scarlet fever, or a drug reaction, guiding further assessment and testing.

How to Approach the Question

This is a factual recall question that tests knowledge of pathognomonic (uniquely characteristic) signs of diseases.
First, identify the key term in the question stem: 'Koplik spot'.
Next, access your knowledge base of common infectious diseases and their hallmark signs.
Systematically evaluate each option: A) Mumps is known for parotitis (swollen salivary glands). B) Measles is classically associated with Koplik spots. C) Pertussis is known for the 'whooping' cough. D) Diphtheria is known for the pharyngeal pseudomembrane.
Based on this direct association, conclude that Koplik spots are the typical sign of Measles.

Concept Tested & Keywords

QTcLjT0EhgF_fqfSMjnuoY

E6 Medicine Harrison 22e Part 1 p. 1682-1684

E6 Nelson Textbook of Pediatrics(2024) — Volume 1 p. 1965-1967

E6 Parks TextBook of Preventive & Social Medicine part 1 — Subpart A (pp 26-201 of 604) p. 150-152

Practise the full NHM MP Staff Nurse - 2015

Attempt every question from this paper in a timed mock, then review the full solution for each one.