Causes
- Idiopathic:
The exact cause is not known of Skin manifestation in COVID-19.
- Certain virus causes skin rash:
It’s common for virus to produced skin rashes. Measles, chickenpox and herpes are examples of viral infections with distinctive rashes - the result of the inflammation caused when the immune system fights the infection within the skin’s cells. On the basis of these viral infections with different skin rashes, COVID-19 could generate a similar skin reaction in some patients.
- Immune system:
The inflammatory changes occur in the skin when the immune system fights the infection within the skin’s cells and that can cause the skin manifestation.
- Changes in blood vessels due to:
Vascular damage can occur due to COVID-19 such as damage to endothelium due to inflammation of blood vessels and alteration in blood coagulation. These cause the thrombotic changes in blood vessels which lead to acro-ishaemic manifestation on skin.
- Drug-induced:
Different drugs which are used in the treatment of COVID-19 can cause mild to severe side effects including different kind of skin rash apart from other systemic side effects.
SEVERAL TYPES OF SKIN RASHES SEEN IN COVID-19 PATIENTS
- A study in China reported that Skin rashes were present in only 0.2 percent of more than 1,000 COVID-19 patients
- A smaller study in Italy reported that the prevalence of skin rashes was 20.4 percent.
Study on skin manifestation in COVID-19
375 cases were observed for skin manifestation in this study. Study showed 5 types of skin manifestation which are mentioned below.
- A macula-papular rash: (47%)
Most common rash observed in the study. These rashes covered 47 % of all skin rashes.
- A rash on hands and feet that looks like Chilblains (The so-called Covid-19 toes): (19%)
- 3A hives-like rash: (19%)
These were observed in 19% of cases. They are consisted of small, slightly elevated reddish or white patches on skin.
- A blistery rash: (9%)
It was found in 9 % of the cases. Consisting of tiny, similarly shaped blisters, this rash was found on the abdomen or back of some patients and on the arms or legs of others.
- Livedo (also known as necrosis): (6%)
It was found in 6% cases. A sign of poor blood circulation, this rash was characterized by purplish skin with a lace-like pattern.
CHARACTERISTICS ASSOCIATED WITH EACH CLINICAL PATTERN
Type of eruption: Pseudo-chilblain
Age: Younger age
Duration: 12.7 days
Stage of COVID-19: Less severe disease
Area involved: Hands and feet
Survival: 100%
Type of eruption: Vesicular
Age: middle-aged patients
Duration: 10.4 days
Stage of COVID-19: medium severity
Area involved: Trunk and limbs
Survival: 100%
Type of eruption: Urticarial rash
Age: middle-aged patients
Duration: : 6.8
Stage of COVID-19: more severe COVID‐19
Area involved: Trunk and few on palm
Survival: 100%
Type of eruption: Maculopapular
Age: middle-aged patients
Duration: 8.6
Stage of COVID-19: more severe COVID‐19
Area involved: Limbs and dorsum of hand
Survival: 98%
Type of eruption: Livedoid or necrotic lesions
Age: Older age
Duration: 9.4
Stage of COVID-19: more severe COVID‐19
Area involved: Trunk or Acral region
Survival: 90%
CONCLUSION
- The researchers have concluded at certain level that some of these eruptions or rashes are actually due to the effect of COVID-19 and can be use as diagnostic for COVID-19, whereas some are not useful for diagnostic purpose due to other cause rather than COVID-19.
- Pseudo-chilblain and vesicular lesions may be useful as indicators of disease.
- Urticarial lesions may be due to many causes so they are unlikely to lead to the diagnosis.
- Maculopapular lesions such as the pseudo vesicular type and those resembling erythema elevatum diutinum or erythema multiforme could lead to suspicion of a diagnosis.
- Livedoid or necrotic lesions are probably not useful for diagnosis. As they are due to vascular damage due to COVID-19.
NOTE: The more study is needed with help of large number of samples in this area of skin manifestation and COVID-19 to reach a firm conclusion.