Quincke Sign

Original Editor - Umamah Ejaz
Top Contributors - Umamah Ejaz, Rachael Lowe, Ewa Jaraczewska and Rishika Babburu

Introduction

Nail beds

Quincke's sign, also known as Quincke's pulse, refers to the visible pulsation of a reddish coloration in the nail bed, typically observed with each heartbeat. This sign can become more apparent by gently pressing on the nail bed to cause blanching, which enhances the visibility of the pulsatile flow.

It is named after Dr. Heinrich Quincke, a German physician who first described the phenomenon in 1868. In addition to this discovery, Dr. Quincke made several other significant contributions to medicine, including the identification of angioedema, the development of the lumbar puncture technique, and the description of idiopathic intracranial hypertension.

Purpose

The purpose of observing Quincke’s pulse is to identify a clinical sign indicative of severe aortic valve insufficiency. This sign, visible as alternating blushing and blanching of the nail bed capillaries, helps detect the presence of a widened pulse pressure, which results from increased systolic stroke volume and decreased diastolic pressure due to regurgitant blood flow into the left ventricle. Recognizing Quincke’s pulse can aid in the early detection and diagnosis of significant aortic regurgitation. In addition to its presence in the nail bed, Quincke’s sign has also been reported on a Janeway lesion in a patient with infective endocarditis, further highlighting its diagnostic value in identifying underlying cardiovascular pathology.This broader presentation highlights its diagnostic value in identifying underlying cardiovascular pathology and underscores the importance of thorough physical examination in patients with suspected valvular heart disease.

Clinicians usually check for Quincke's sign as part of a broader cardiovascular exam that includes looking for other peripheral signs of aortic regurgitation like Corrigan's pulse, Hill's sign, and de Musset's sign. Finding several of these signs together makes it more likely that the patient has significant aortic insufficiency and needs an echocardiogram for further evaluation. It's worth noting that while Quincke's sign is fairly specific for severe aortic regurgitation, it can occasionally show up in other conditions with high cardiac output, such as an overactive thyroid, severe anemia, or arteriovenous fistulas.

Technique

1. Patient Positioning: Ask the patient to sit comfortably with their hand resting at heart level to ensure proper circulation and visibility.
2. Nail Bed Exposure: Select a finger (usually the index or middle finger) and make sure the nail bed is clean, well-lit, and free of any nail polish or injury.
3. Apply Gentle Pressure: Using a clear object like a glass slide or your finger, apply light, even pressure to the tip of the nail enough to blanch the nail bed without causing discomfort.
4. Observe for Pulsations: Look closely for alternating flushing (reddening) and blanching of the nail bed with each heartbeat. This indicates capillary pulsation.
5. Enhance with Illumination (if needed): Use a penlight or focused illumination to enhance visibility of the pulsation, especially in low-light environments or in patients with darker skin tones.

A positive Quincke’s sign supports the suspicion of aortic regurgitation and should prompt further cardiovascular evaluation, such as auscultation and echocardiography

The following without shows how to observe the sign;

Evidence

Quincke’s sign has low sensitivity and specificity (both <10%), and current evidence shows little correlation between its presence and the severity of AR, based on limited and low-quality data. In the Framingham study, the sign was observed in 4.9% of the general population, while only 0.5% had moderate to severe aortic regurgitation, indicating it is neither common nor specific to AR. Importantly, Quincke’s sign is not pathognomonic. Similar findings can appear in other conditions. For instance, a “pseudo-Quincke pulse” has been reported in a patient with keratoderma, where nail bed compression from sclerodactyly mimicked the appearance of the sign.

In summary, while Quincke’s sign can suggest the possibility of aortic regurgitation, it should not be used alone for diagnosis. Objective tests, such as echocardiography, are essential to confirm the presence and severity of the condition before making clinical decisions.