Acute Centro-facial Pigmentation – A sign of Viral Exanthem ? : Case Reports

We report two cases of abrupt onset centro-facial pigmentation associated with acute viral fever and arthralgia. Review of literature yielded reports of similar pigmentation along with other dermatological manifestations like maculopapular rash, vesiculobullous lesions etc. In our cases centrofacial pigmentation confined to nose was the only presenting symptom and required treatment from patient’s perspective. Centro-facial melanosis may be considered as a sign of acute viral fever which could require specific treatment. The aim of our report is to widen the vision of clinicians in considering abrupt onset of centro-facial melanosis as a presenting symptom in an acute sero-negative viral fever with arthralgia.


Introduction
A large variety of skin and mucous membrane lesions have been reported in associa on with acute viral illness.The most common cutaneous manifesta on described in acute viral exanthema is generalised maculopapular erup on followed by aphthous ulcers and cutaneous pigmenta on.We report two cases of acute centrofacial pigmenta on as the only cutaneous manifesta on in viral illness.

Case 1
A 54 years old female presented with pigmenta on of nose since 2 days.The pigmenta on was preceded by a high grade, con nuous fever with malaise and joint pains of 4 days.The pigmenta on was abrupt in onset, asymptoma c and without previous history of rash.There was no history of excessive sun exposure, no history of usage of local irritants such as vicks vaporub, zandu balm (which is a very common prac ce in India for rhini s, sinusi s, and headache).No history of drug intake and alterna ve therapy.The pa ent is a non diabe c, non hypertensive and not on any oral medica ons and supplements.
On examina on, the pa ent was febrile.Dermatological examina on revealed blotchy, uniform dark brown macules over the bridge of nose extending over the sides (Fig 1).There were no similar pigmentary changes on any other part of the body apart from the nose.No evidence of erythematous maculopapular erup ons on other areas.Oral mucosa, conjunc va, genitalia, palms and soles were normal.
A clinical diagnosis of acute febrile illness associated with centro-facial pigmenta on was made.In view of the high prevalence of viral infec ons, par cularly dengue and chikungunya fever in south India, pa ent was advised to undergo specifi c serological inves ga ons.The pa ent was symptoma cally treated with an -pyre c, so diet and rest.
The pa ent was reviewed 3 days later with blood reports which showed mild leucopenia, neutropenia, mild lymphocytosis, basophilia and mild reduc on in platelet counts.NS1 an gen for dengue and chikungunya specifi c IgM, IgE an bodies were nega ve.The pa ent was afebrile with severe arthralgia, unable to perform daily ac vi es.No new pigmenta on was observed at other areas apart from nose and no viral exanthem like lesions were present.
With the constella on of presen ng symptoms and laboratory blood picture, the diagnosis of centro-facial melanosis with acute febrile illness of viral ae ology was made, although the specifi c serological tests were nega ve.The pa ent was extremely self conscious due to hyperpigmena on of nose and seeked remedy for the same.The pa ent was advised spot applica on of Kligman formula (2% hydroquinone, 0.05% tre noin, 0.01% fl uocinolone acetonide) cream at night and licorice-arbu n combina on cream in the morning along with regular repeated applica on of broadspectrum sunscreen for 1month.
The pa ent followed up a er a month.The pigmenta on over nose had improved but was s ll present (Fig 2).She complained of persistent joint pain.She was advised to con nue licorice-arbu n cream along with sunscreen, analgesics for joint pains and to follow up a er a month.

Case 2
A 61 years old non diabe c, non hypertensive male presented with pigmenta on over the nose since 2 weeks.History revealed that the pa ent had fever, malaise and joint pains 3 weeks back for which he was treated symptoma cally with analgesics and anpyre c.One week later pa ent no ced abrupt onset of asymptoma c pigmenta on over the nose without previous history of rash.No history of drug intake, sun exposure, usage of local irritants prior to pigmenta on.Dermatological examina on revealed blotchy dark brown macules on bridge of nose extending on to the sides and ala of nose (Fig 3).Oral mucosa, conjunc va, genitalia, palms and soles were normal.
A provisional diagnosis of centro facial melanosis as a sequela to an acute viral illness was made.The pa ent was treated with Kligman formula at night and licorice-arbu n cream in the morning along with a broad-spectrum sunscreen for a month and is due for followup.

Discussion
A large variety of skin and mucous membrane lesions have been documented to occur in associa on with acute viral illness.A generalised maculopapular erup on is the most common cutaneous manifesta on described in acute viral exanthem such as chikungunya 1,2,3 and dengue followed by aphthous ulcers and cutaneous pigmenta on.Other less common presenta on includes vesicobullous lesions (par cularly in children) 4 , xerosis and scaling, desquama on of palms, soles and face, excoriated papules, generalised erythema, transient nasal erythema, cutaneous necro c ulcers, ecchymosis, generalized ur carial lesions and even exacerba on of pre exis ng dermatoses 4 .
Pigmentary changes have been one of the common presenta ons in viral illness 1,2,3,4,5 .Mechanism of pigmenta on can be post infl ammatory 5 .An increase in intraepidermal melanin dispersion/reten on triggered by the virus has also been suggested 6 .An exposure to ultraviolet rays in case of pigmenta on in exposed areas may be contributory 3,6 .With the s mula on of re culo-endothelial system by chronic infec ons and consequent reduced adrenocor cal ac vity, enhanced pigmenta on of skin has been stated 7 .
Inamadar AC et al 6 has reported asymptoma c brownish-black pigmenta on, predominantly involving centrofacial area as the most common cutaneous feature observed amongst suspected cases of chikungunya in their observa onal study.Shivakumar V et al 7 has reported an abrupt onset of unusual facial melanosis in viral fever without any preceding symptoms.Riyaz N et al 5 observed a striking nose pigmenta on in a large number of pa ents and hence suggested to consider this peculiar pigmenta on as a marker for chikungunya fever and proposed a "chik sign."Kalane S et al 8 reported congenital chikungunya with centro-facial pigmenta on.Bandyopadhya D et al 1 has stated delayed cutaneous manifesta on in a form of hyperpigmenta on which may persist for months a er remission of chikungunya.In our cases, abrupt onset centro-facial melanosis was the only cutaneous manifesta on which presented and persisted for more than a month.

Conclusion
The aim of our case reports is to widen the vision of clinicians in considering abrupt onset of centro-facial melanosis as a presen ng symptom in an acute seronega ve viral fever with arthralgia -a viral exanthem.

Fig 1 :
Fig 1: A 54 years old female with nose pigmenta on of 2 days dura on.