Keywords

Pseudo-vesicular, pityriasis rosea, atypical Pityriasis rosea (PR) continues to elude dermatologists with its controversial etiology and atypical presentations even after two centuries since it was first described. The literature is flooded with reports of increasingly diverse morphology and distribution of lesions associated with this condition.

Abstract: Pityriasis rosea (PR) is an acute, self-healing exanthema characterized by oval erythematous-squamous lesions of the trunk and limbs

Case Report

A 29-year-old female with 2½ months of amenorrhea (G₃P₀L₀A₂) presented with asymptomatic, reddish, raised lesions over the trunk and extremities of 2 days duration. The lesions first appeared on the right breast and in the following 2 days, similar lesions appeared over the trunk and proximal extremities. Patients also complained of fever prior to the appearance of skin lesions. There was no history suggestive of preceding upper respiratory tract infection, abdominal complaints, arthralgia, myalgia, malaise and headache. She was taking no medication other than routine supplements prescribed for pregnancy. She had history of first trimester abortion in the previous two pregnancies, but never had any skin rash during the corresponding period of loss of pregnancy. Patient was febrile (100⁰F), but vitals were stable and general examination showed no positive findings. Cutaneous examination revealed multiple bilaterally symmetrical, infiltrated, erythematous, nonscaly papules and plaques with pseudo-vesicular surface present on the chest, abdomen, back, pubic area and proximal thighs (Fig. 1 a-c). The lesions had coalesced to form larger plaques but the smaller ones showed some orientation along the lines of skin cleavage, especially over the lateral areas of trunk and back. Mucosa was spared, and scalp, genitals, hair and nails were unremarkable. Systemic examination showed no abnormality. We considered a differential diagnosis of Sweet syndrome and atypical PR. The previous history of first trimester abortions led us to think of an underlying antiphospholipid antibody syndrome (APLAS). Erythrocyte sedimentation rate (ESR) and hemogram were normal except for mild neutrophilia (81%), but without any rise in total leukocyte count. Blood sugar, urine routine, microscopy and liver, renal and thyroid function tests were within normal limits. Human immunodeficiency virus - enzyme-linked immunosorbent assay (HIV-ELISA), hepatitis B surface antigen (HBsAg) and Venereal Disease Research Laboratory (VDRL) tests were negative. Sonography showed a single live fetus with no anomalies. Antinuclear antibodies (ANA) and anti-ds-DNA were negative. Likewise, the antibodies against lupus anticoagulant, cardiolipin and β₂-glycoprotein were also negative, thus ruling out APLAS. Skin pathergy test was negative.

Histopathology of skin lesions showed very subtle patchy spongiosis in the stratum spinosum and superficial dermal infiltration with lymphocytes, neutrophils and occasional eosinophils (Fig. 2 a-c). The patient was treated symptomatically with antihistamines and topical calamine lotion. Interestingly, the patient showed significant resolution of lesions 1 week following the first visit. The lesions had flattened and all that remained was minimally pigmented macules and patches with few areas showing slight erythema as well (Fig. 3 a-c). This event shifted the final diagnosis in favor of PR.

Discussion

Pityriasis rosea is an acute, self-healing exanthema characterized by oval erythematous-squamous lesions of the trunk and limbs, usually sparing face, scalp, palms and soles.¹ Variations from this classical description are known to be fairly common, but difficult to quantify.² The incidence of the herald patch varies from 40% to 76%, and similar to our patient, its absence does not exclude the diagnosis.³ Although vesicular lesion has consistently been reported as one of the atypical presentations of PR, to the best of our knowledge, no case of PR presenting as pseudo-vesicles has been previously published. Purpuric or hemorrhagic, and urticarial variants have also been commonly reported.¹ Other rarer types include large patches (PR gigantea of Darier) and papular PR.^1,3 Sites such as face, axillae and groins are predominantly involved in PR inversus.³ Involvement of mucous membranes is not uncommon.⁴

The simplest and most accurate description of the characteristic orientation of secondary eruptions should be “along lines of skin cleavages”.⁵ On careful examination, we noticed a similar pattern in our patient. Clichés associated with descriptions of the orientation such as “Christmas-tree”, “inverted Christmas-tree”, “fir tree” and “parallel to the ribs” are imprecise and probably obsolete.^3,5 The age of our patient and the time of outbreak of the rash correspond to a recent epidemiological study in the country.⁶ Out of 200 cases reported in the study, only one patient presented with PR during pregnancy. Reports of PR in pregnancy in Indian literature are infrequent. However, Corson et al⁷ in 1950 reported that PR is more common during pregnancy as compared to the general population (18% vs. 6%), but this finding has not been corroborated by subsequent studies.

Sweet’s syndrome patients appear dramatically-ill, whereas our patient had no constitutional signs and symptoms. Although classical Sweet’s is known to occur in pregnant females, but absence of features like mucosal lesions, systemic involvement, leukocytosis and confirmatory histopathology diminished the odds even further.^8,9 Without therapeutic intervention, patients with classical Sweet’s may show resolution of lesions, but this usually takes weeks or months.¹⁰ On the other hand, self-resolution is the rule in PR and this may take an average of 45 days.¹ Our patient showed signs of resolution in about 10 days from onset of rash. Cases with similar course i.e., remission within 2 weeks of appearance of rash have been reported in the past.¹

A recent study¹ suggests that PR developing during pregnancy may be followed by premature delivery and even fetal death. The total abortion rate reported was 13%, but it reached a staggering 57-62% if PR developed within 15th week of gestation. The authors recommended a closer follow-up for women who develop PR during the first 15 weeks of gestation, especially with atypical forms. Other than the PR episode, so far the pregnancy period in our patient has been uneventful. Nonetheless, due to the above mentioned risks and given her previous history of abortions, we are closely monitoring her for occurrence of any adverse event.

Acknowledgments

We thank Dr Rajiv Joshi for his constant support to our department through his impeccable histopathological and clinical skills.

References

1. Drago F, Broccolo F, Javor S, Drago F, Rebora A, Parodi A.Evidence of human herpesvirus-6 and -7 reactivation in miscarrying women with pityriasis rosea. J Am Acad Dermatol. 2014;71(1):198-9.
2. Chuh A, Zawar V, Lee A. Atypical presentations of pityriasis rosea: case presentations. J Eur Acad Dermatol Venereol. 2005;19(1):120-6.
3. Chuh A, Lee A, Zawar V, Sciallis G, Kempf W. Pityriasis rosea - an update. Indian J Dermatol Venereol Leprol. 2005;71(5):311-5.
4. Drago F, Broccolo F, Rebora A. Pityriasis rosea: an update with a critical appraisal of its possible herpesviral etiology. J Am Acad Dermatol. 2009;61(2):303-18.
5. Chuh AA. Rash orientation in pityriasis rosea: a qualitative study. Eur J Dermatol. 2002;12(3):253-6.
6. Sharma L, Srivastava K. Clinicoepidemiological study of pityriasis rosea. Indian J Dermatol Venereol Leprol. 2008;74(6):647-9.
7. Corson EF, Luscombe HA. Coincidence of pityriasis rosea with pregnancy. AMA Arch Derm Syphilol. 1950;62(4):562-4.
8. Cohen PR, Kurzrock R. Sweet’s syndrome revisited: a review of disease concepts. Int J Dermatol. 2003;42(10):761-78.
9. Dabade TS, Davis MD. Diagnosis and treatment of the neutrophilic dermatoses (pyoderma gangrenosum, Sweet’s syndrome). Dermatol Ther. 2011;24(2):273-84.
10. Cohen PR, Kurzrock R. Sweet’s syndrome: a neutrophilic dermatosis classically associated with acute onset and fever. Clin Dermatol. 2000;18(3):265-82.