Psoriasis is a common, chronic, immune-mediated inflammatory skin disease of unknown cause. Although psoriasis is usually not life threatening, generalized pustular psoriasis of pregnancy is a rare and severe variant of pustular psoriasis, also called impetigo herpetiformis, and that can be life threatening. Patients are frequently pyrexic and systemically ill. Complications include dehydration, septicaemia, hypothermia and hypocalcaemia .
We report a patient with impetigo herpetiformis who had most of the symptoms of systemic disease, presented with hypovolaemic shock and needed critical care treatment.
A 30-year-old multiparous woman (gravida 2, para 2) at the tenth day after her caesarean section operation presented with generalized pustular psoriasis and hypovolaemic shock. She was 165 cm tall and weighed 69 kg. At her last trimester, she was admitted to hospital with a pruritic, painful pustular eruption noted on her genital region, and 48 mg/day steroid therapy was started. She underwent caesarean section operation, and the baby was normal, but 8 days after the operation, pustular lesions appeared on her abdomen and thighs, which subsequently became more generalized. She had associated bilateral shoulder and arm pain without redness or swelling of joints, backache and severe pruritus. Malaise, fever and diarrhoea accompanied her lesions. She and her family had no history of psoriasis, but she had undergone a thyroidectomy operation 13 years previously and after that she had been taking oral calcium supplementation because of the hypocalcaemia.
She was anxious, irritable and confused. On examination, she was found to have an extensive pustular lesion that affected almost her entire body including oral mucosa, head, face, arms, legs, back, hands palmar and plantar regions. She had bilateral cataracts. Her repiration rate was 22/min, temperature 38.5°C, blood pressure (BP) 80/50 mmHg and heart rate l48 beats/min. Her urine output was 20 ml/h.
At admission, there were problems with monitoring. It was difficult to site ECG electrodes, so they had to be secured with additional dressings and, as the patient complained of severe pain with BP cuff inflation and she was haemodynamically unstable, invasive arterial monitoring was considered. The catheter had to be sutured in place. Furthermore, there were problems finding and securing venous access in the presence of widespread pustular skin lesions and peripheral vasoconstriction, so central venous access was established. A slide sheet was used to minimize friction, prevent skin tears and improve comfort. Central venous pressure was 0 cmH2O. Respiratory alkalosis was present without hypoxaemia and chest radiograph was normal.
Laboratory findings included the following values: erythrocyte sedimentation rate 115 mm/h; haemoglobin, 8.0 g/dl; white blood cell count, 18 600 μ/l; platelet count, 888 000 μ/l; serum aspartate amino transferase 47 μ/dl; Ca, 2.81 mg/dl (normal range 8–10.7 mg/dl); phosphate, 7.8 mg/dl (normal range 3–4.5 mg/dl); albumin, 1.2 g/dl (normal range 3.5–5.5 mg/dl), antistreptolysin O titre 185; thyroid hormone levels were normal; parathyroid hormone, 3.56 ng/l; K and Mg levels within normal limits.
Bilaterally on the cheeks, face, head, back, abdomen, arms, legs, buttocks and hands were widely scattered, 1–3 mm, inflamed papules and pustules with poorly defined surrounding erythema. Several were grouped into plaques and some had yellow crust overlaid with excoriation. Skin was exfoliating in layers. The result of a skin biopsy was impetigo herpetiformis.
As the skin barrier was compromised and there was generalized oedema, the standard Parkland formula was chosen to manage the replacement fluid therapy, because the lesions widely infiltrated the skin [the affected body surface area was approximately 90%] and the skin was exfoliating in layers. Twenty percent human albumin had to be added to the therapy. The blood calcium level was corrected, according to the serum albumin level. After haemodynamic stability had been secured, the electrolyte balance was obtained. The patient was seen by psychiatrics because of her anxiety. Short acting anxiolytics and antidepressants were started.
Skin moisturizer containing urea and emollient were applied topically three times a day. Intravenous pheniramine was given when the pruritus was severe. The acute pain team prescribed regular paracetamol and oral tramadol solution as required. Enteral and parenteral nutrition, together, containing 2000 kcal/day was started at the beginning of her therapy. After that, the patient was allowed to eat semi-solid food with additional nutritional supplement given on the advice of the dietician and oral calcium was added to the therapy. Broad-spectrum antibiotics were empirically started at the beginning of the therapy, but all bacterial cultures yielded negative results, so antibiotic therapy was stopped. The patient was treated with oral prednisone started at 1 mg/kg (60 mg/day) and dosage was decreased by 8 mg/week. The patient was referred to the endocrinology department, and hypoparathyroidism was diagnosed. For treatment, calcium 2 g/day and vitamin D was added. The systemic symptoms were subsiding within 20 days and the patient was transferred to the dermatology clinic. At the end of 20 days of treatment, the skin was completely cleared and she was discharged from hospital. She was followed up by the endocrinologists. Eleven months later she was again admitted to our hospital with hypovolaemic shock. The patient had scattered new lesions. She had undergone a cataract operation under local anaesthesia before the skin lesions started. The treatment was managed as before, but in this case, a urinary tract infection was diagnosed and treated. After 3 days of replacement therapy, the skin lesions subsided rapidly; she was transferred to the dermatologists again in order to maintain her long-term therapy.
Impetigo herpetiformis was first described by Hebra  in 1872. Patients with impetigo herpetiformis have been shown to respond dramatically to calcium therapy. On the contrary, some investigators have reported recurrences of impetigo herpetiformis in subsequent hypocalcaemia episodes. Hypocalcaemia is a cause or result of impetigo herpetiformis. This condition is not known. Although there are reports stating that hypocalcaemia might precipitate impetigo herpetiformis, it has been claimed that hypocalcaemia seen in impetigo herpetiformis might be a secondary phenomenon due to hypoalbuminemia or malabsorption conditions seen in impetigo herpetiformis [3–6].
According to Holm and Goldsmith , hypocalcaemia and hypoalbuminaemia seen in impetigo herpetiformis are secondary to the extensive cutaneous inflammation that is the result of extravasations of albumin and albumin-bound calcium to the intestinal space. In our patient, severe hypocalcaemia resulted from the hypoparathyroidism secondary to the subtotal thyroidectomy operation. Severe hypoalbuminaemia was probably due to the loss of albumin in large exudative areas.
Systemic and life-threatening complications include pneumonia, acute renal failure, congestive heart failure, acute respiratory distress syndrome, hepatitis and sepsis secondary to exfoliative dermatitis may be present. We have added hypovolaemic shock to these complications.
In the literature, there are a few cases about the recurrence of this disease . In our case, we decide that previous hypoparathyroidism and chronic hypocalcaemia with the operation stress may exacerbate the recurrence.
1 Oumeish OY, Parish JL. Impetigo herpetiformis. Clin Dermatol 2006; 24:101–104.
2 Hebra F. Relation between pregnancy and dermatologic disorders. Wien Med Wochenschr
3 Wolf Y, Groutz A, Walman I, et al
. Impetigo herpetiformis during pregnancy: case report and review of the literature. Acta Obstet Gynecol Scand 1995; 74:229–232.
4 Moynihan GD, Ruppe JP. Impetigo herpetiformis and hypoparathyroidism. Arch Dermatol 1985; 121:1330–1331.
5 Thio HB, Vermeer BJ. Hypocalcaemia in impetigo herpetiformis: a secondary transient phenomenon? [Letter]. Arch Dermatol 1991; 127:1587–1588.
6 Ott F, Krakowski A, Tur E, et al
. Impetigo herpetiformis with lowered serum level of vitamin D and its diminished intestinal absorption. Dermatologica 1982; 164:360–365.
7 Holm AL, Goldsmith LA. Impetigo herpetiformis associated with hypocalcaemia. Arch Dermatol 1991; 127:91–95.
8 Sahin HG, Sahin HA, Metin A, et al
. Recurrent impetigo herpetiformis in a pregnant adolescent: case report. Eur J Obstet Gynecol Reprod Biol 2002; 101:201–203.