All stages of rashes are seen simultaneously in?

Appeared in: JODHPUR AIIMS SNO-2018

Explanation

Chickenpox is characterized by a pleomorphic rash, meaning lesions in various stages of development (macules, papules, vesicles, and crusts) are present at the same time.
This occurs because the rash appears in successive crops over several days, leading to a mixed appearance of lesions.
The provided image clearly shows this pleomorphism, with a mix of red spots, fluid-filled blisters, and crusted scabs on the patient's back, which is pathognomonic for chickenpox.

Option A: The rash of typhoid fever consists of 'rose spots,' which are faint, salmon-colored macules, primarily on the trunk. It is not a vesicular or pleomorphic rash.
Option C: The measles rash is maculopapular and spreads from the head downwards (cephalocaudal). The lesions in a specific area are typically in the same stage of development and become confluent.
Option D: The rash of smallpox is monomorphic, meaning all lesions progress through the stages of macule, papule, vesicle, and pustule synchronously. This is a key feature that distinguishes it from chickenpox.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Characteristics of exanthematous rashes as background academic context rather than a clinical decision trigger.
Recognizing a pleomorphic rash is crucial for the prompt diagnosis of chickenpox and initiating appropriate infection control measures, such as airborne and contact precautions, to prevent transmission.
Nurses should educate patients and families on managing symptoms like itching (with calamine lotion, oatmeal baths) and preventing secondary bacterial infections by keeping nails short and avoiding scratching.
What if? If the rash were monomorphic (all lesions at the same stage) and predominantly on the face and extremities (centrifugal), smallpox would be a primary concern, requiring immediate public health notification and strict isolation, as it is a high-consequence disease.

How to Approach the Question

First, identify the key phrase in the question: 'All stages of rashes are seen simultaneously'.
Recognize that this phrase describes a 'pleomorphic' rash.
Systematically review the rash characteristics associated with each disease listed in the options.
Associate the term 'pleomorphic rash' with chickenpox, where new lesions appear in crops over several days.
Contrast this with the 'monomorphic' rash of smallpox (all lesions in the same stage) and the maculopapular rashes of measles and typhoid to confirm the correct answer.

Concept Tested & Keywords

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E6 Parks TextBook of Preventive & Social Medicine part 1 — Subpart A (pp 26-201 of 604) p. 147-149

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