Gianotti-Crosti-Syndrom nach Impfung

Infectious exanthemas in childhood

Most childhood exanthemas are harmless. However, recognizing serious diseases with life-threatening complications at an early stage is important for the timely initiation of adequate therapy. This requires knowledge of the specific patterns of the exanthema, obtained from the medical history and the clinic, including the patient's general condition and physical examination. In unclear cases, additional diagnostic measures are undertaken, such as blood tests and smears (cutaneous, mucocutaneous). Viruses are the most common cause of childhood exanthemas. New variants of infectious agents, improved diagnostics and stays in tropical and subtropical countries have expanded the spectrum of infectious exanthemas.

Viral exanthems in children: A great imitator

Viral exanthems are frequent in children and are mostly self-limited. Early recognition and differentiation from other childhood illnesses are important to direct further investigations and treatment initiation. The clinical presentation of viral exanthems in children includes a polymorphic spectrum of skin eruptions ranging from classic viral exanthems to "atypical" presentations that can mimic nonviral diseases; thus, viral exanthems of childhood can be readily diagnosed on clinical grounds, but not rarely do they represent a diagnostic challenge. In this review, we focus on viral diseases in children that may be difficult to diagnose due to their clinical similarities with nonviral diseases, and we offer clues for the differential diagnosis and proper diagnostic testing in such cases.

[Paraviral exanthems]

Paraviral exanthems are distinct skin diseases due to infections with different viruses. Although no virus has been identified so far in some exanthems, the main age of manifestation, the clinical course of the exanthem, and the extracutaneous symptoms are suggestive for a viral genesis. While many viral infections are a direct result of the infection, paraviral exanthems reflect the response of the immune system to the infectious pathogens. Viruses cannot be identified in the skin. Typical paraviral exanthems include Gianotti-Crosti syndrome, pityriasis rosea, pityriasis lichenoides, papular-purpuric gloves and sock syndrome, and asymmetrical periflexural exanthema. Unilateral mediothoracic exanthem, eruptive pseudoangiomatosis are rare and eruptive hypomelanosis has been described recently.

Acral manifestations of systemic diseases: Drug-induced and infectious diseases

Drug reactions and systemic diseases often involve the skin. In particular, most drug-induced reactions and many infectious diseases present with dermatologic manifestations localized acrally, that is on distal portions of limbs (hand, foot) and head (ears, nose). A detailed review of all acral dermatologic signs of drug reactions and systemic diseases is beyond the scope of this paper, although some of these disorders will be discussed specifically here.

Giannoti-Crosti syndrome associated with type A influenza

Gianotti-Crosti syndrome is an entity characterized by an acute papular eruption in children and has been associated with a multitude of viruses. This is the first case reported in association with type A influenza, a virus that usually has no dermatologic findings.

Gianotti-Crosti syndrome following hepatitis A vaccination

We report a case of Gianotti-Crosti syndrome in a child following hepatitis A vaccination in order to insist that currently available hepatitis A vaccines are highly immunogenic and that Gianotti-Crosti syndrome is a possible minor adverse reaction.

Gianotti-Crosti syndrome in a child following hepatitis B virus vaccination

Gianotti-Crosti syndrome is self-limited, characterized by papular eruption with a symmetrical distribution on the limbs and face of children, and a dermatosis of unknown etiology. However, there are many suggested factors such as a number of diseases (viral or bacterial) and vaccination. We report a case of Gianotti-Crosti syndrome that had developed 3 weeks after the hepatitis B virus vaccination.

[Viral exanthem]

The most frequent cause of exanthematous diseases are viral infections, which provoke skin alterations either directly or via the reaction of the immune system. In many distinct parainfectious clinical pictures, several viruses from quite different groups are able to produce a specific exanthem. Dominant pathogens for exanthematous diseases include non-polio enteroviruses, respiratory viruses, Epstein-Barr virus, HHV-6 and HHV-7 viruses as well as parvovirus B19. In many cases exanthemata present with maculate or maculopapular features in disseminated distribution. Some exanthematous diseases exhibit typical predilection sites. In addition to the clinical picture, diagnosis is based on the patient's history, observation of the patient's general condition, awareness of the season in the year, and physical examination. In uncertain cases and for scientific studies, blood analysis, smear tests, and histological investigation confirm the diagnosis. Knowledge of exanthematous disease, which usually run harmless course, is essential for differentiation of life-threatening disorders. This article presents exanthematous viral diseases depending on age at primary manifestation.