Introduction

Miliaria, or eccrine miliaria, is a frequently seen skin disease triggered by blocked eccrine sweat glands and ducts, causing backflow of eccrine sweat into the dermis or epidermis wich results in a rash comprising sweat-filled vesicle formation under the skin, it is most common in warm, humid climates during the summer months [1]. The 3 main types of miliaria are crystallina, rubra, and profunda and are classified by the depth of obstruction of the sweat duct causing clinical and histological differences. We report a case of miliaria crystallina.

Materials & methods

A 15-year-old girl hospitalized in intensive care following a neurosurgical procedure presented with a vesicular rash consisting of fine, generalized blisters involving the trunk, neck and limbs. The hospitalization was complicated by a systemic infection which was responsible for prolonged fever, on the thrid day of the fever, the patient developed a non-pruritic, clear fluid-filled vesicular rash without erythema the lesions, which resembled water droplets (Figure 1), resolved spontaneously within 72 hours after reducing skin temperature and humidity. Based on the macroscopic characteristics as well as the self-limiting nature of the rash, the diagnosis of miliaria crystallina was clinically established [2].

Results

Miliaria crystallina appears as 1 to 2 mm superficial vesicles, affecting both adults and neonates usually younger than 2 weeks old. Since the pathophysiology involves the most superficial layer of the epidermis, the stratum corneum, the vesicles have a thin superficial layer [3]. This results in the vesicles resembling water droplets on the skin that easily rupture. The vesicles are superficial; therefore, an inflammatory response is typically absent. The upper trunk, neck, and head are the most commonly affected sites. The rash will usually appear within a few days of exposure to risk factors and will resolve within a day after the superficial layer of skin rubs off. With hot, sweaty conditions being the main risk factors for miliaria, general measures to decrease sweating, and eccrine duct blockage are warranted in the management of miliaria. This includes cooler environments, wearing breathable clothes, exfoliating the skin, removing skin occluding objects such as bandages or patches, as well as treating febrile illnesses.

Figure 1: Fine vesicular rash.

Conclusion

Miliaria is a generally benign skin disorder that occurs in patients of all ages and genders who are exposed to humid, warm climates. It is usually self-limited and resolves spontaneously in response to a cooler, dryer atmosphere.

References

1. Guerra KC, Toncar A, Krishnamurthy K. Miliaria. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing. 2024. Disponible sur: http://www.ncbi.nlm.nih.gov/books/NBK537176/.
2. Haas N, Martens F, Henz BM. Miliaria crystallina in an intensive care setting. Clin Exp Dermatol. janv 2004; 29(1): 32‑4.
3. El Anzi O, Hassam B. Widespread miliaria crystallina: about a case. Pan Afr Med J. 2018; 30: 69.