Pemphigus vulgaris in a neonate

Pemphigus vulgaris (PV) is a common blistering disease in Western countries but neonatal pemphigus (NP) is rare.^1,3,5,6 It is characterized by multiple skin and mucosal erosions and is caused by tranplacental passage of maternal antibodies against desmoglein.³ It heals spontaneously in two to three weeks.

CASE

A 3-hour-old baby boy was referred with multiple skin erosions on the left side of the neck, upper left chest and groin without oral involvement (Figure 1A). He was born by normal vaginal delivery without complication with an APGAR score of 8 and 9 at 1 and 5 minutes, respectively, and a weight of 2.57 kg. His mother was known to have PV since 1999, which was proven by biopsy and immunofluorescence. The product of her first pregnancy in 1999 was a baby boy with multiple erosions. The first baby was diagnosed with NP based on the results of a skin biopsy and immunofluorescence. The erosions healed spontaneously in two weeks. The mother was treated with prednisone, and later dapsone was added. She went into complete remission. She went off treatment in July 2001 and developed a new flare of PV in June 2005 during her second pregnancy. She was treated with prednisone 40 mg every other day. Physical examination of the second baby showed multiple erosions over the left side of the neck, shoulder and groin. Skin biopsy was refused by the parents and indirect immunofluorescence showed 1:10. He was treated with topical fucidin and 1% hydrocortisone, and discharged three days after delivery in good condition. At the age of four weeks, he had complete clearance (Figure 1B).

Figure 1a.

At birth, multiple eroded vesicles at upper chest and left side of the neck.

Figure 1b.

At age four weeks with complete healing.

DISCUSSION

PV is the most common form of pemphigus.⁵ It is usually seen in the fifth decade of life.^2,5 Neonatal PV is a rare disease^1,3,6 seen soon after birth and characterized by cutaneous, mucosal or mucocutaneous erosions. PV is diagnosed by histological and immunofluorescence studies. Routine histology will show epidermal basal cell vacuolization and spongiosis with exocytosis of polymorphonuclear leucocytes and eosinophils. Immunofluorescence will show IgG and C3 deposition. Indirect immunofluorescence is positive in patients with active disease. A high titre indicates active disease. ² It usually resolves spontaneously in 2 to 3 weeks.^{2–5,7,9,12,13,19–21}

Neonatal PV results from transplacental passage of IgG maternal autoantibodies, mainly class 4, against desmoglein 3 (Dsg3), a transmembrane glycoprotein of the cadherin family.^{1,3,4,5,7,8,11,20,23–27} More than 21 cases of neonatal PV have been reported (Table 1), with the first proven one in 1975 by Rucco et al.²⁸ However, there are only 3 reported cases of pemphigus foliaceus (PF).^15–17 This difference in incidence may be related to the distribution of Dsg1 and 3 in neonatal skin. Dsg1, the protein affected in PF, is present throughout the epidermis in both adults and neonates, while type 3 is present in the basal and intermediate suprabasal layer in adults, but throughout the epidermis in neonates. So the frequency of neonatal PF is less than PV in babies born to mothers with pemphigus based on the desmoglein compensation theory.^5,18 This is supported by at least 18 cases of pregnant women with PF who delivered babies free of the disease.^29,30 There is no correlation between the titer of maternal PV antibodies and the presentation of the disease in neonates.^2,5,6 This is supported by cases of neonatal PV from mothers with no active disease^5,9,31 and cases of healthy neonates born to mothers with highly active disease.^{4–6,16,17,32–36} The mother might have only oral disease while the baby has both oral and cutaneous involvement.^5,36 Stillbirths have been also reported. ^23,24,31

Table 1.

Reported cases of neonatal pemphigus vulgaris.

Reference number	Mother’s Disease	Recovery Duration	Treatment	DIF**	IDIF*	Site	Sex
1	Severe	2 weeks	Like above	IgG and C3	1/160	Skin and oral cavity	F
3	Mild	2 weeks	Emollient and mupirocin	IgG and C3	1/160	Skin and tongue	F
6	Unknown	2 weeks	Like above	NA	NA	Skin	F
7	Mild	2 weeks	Like above	IgG and C3	1/160	Skin	M
8	Unknown	3 weeks	Like above	NA	1/20	Skin	F
9	Mild	2 weeks	No treatment	IgG and C3	1/40	Skin and occipit	M
10	Mild	2 weeks	Emollient and mupirocin	IgG and C3	1:80	Skin	F
12	Severe	2 weeks	No treatment	IgG	1/20	Oral	M
13	Mild	3 weeks	No treatment	NA	1/20	Skin, tongue and scalp	F
15	Unknown	3 weeks	Like above	IgG	1/32	Skin and occipit	M
22	Mild	2 weeks	No treatment	IgG	NA	Skin	F
34	Unknown	2 weeks	Like above	IgG and C3	Neg	Skin and scalp	F

^*Indirect immunoflurescence

^**direct immunoflurescence

Rx: treatment, NA: Not available, Neg: negative result, M: male, F: female