Diseases for which the actiopathogenic mechanisms have not so far been adequately defined have been grouped in this chapter. Crying, problems with feeding, rashes, and an occasional fever are common. These problems become health concerns only when they are extreme—for example, when children cry too much, when they are not growing well (see Failure to Thrive), or when they have high fevers that do not go away.
Pityriasis Alba : This disease manifests as ill-defined, hypopigmented macules of varying sizes occurring chiefly on the face of children. This disease is more common in the colder climates. The lesions are asymptomatic and keep on lisappearing spontancously and reappearing till the child atains adulthood. It does not occur in the adults It is generally believed to be caused by saprophytic staphylococci.
Pityriasis Rosea : This disease is common in the young adults and manifests as a sudden eruption of asymptomatic, 1-2 cm oval or circular, annular lesions which have a pinkish periphery and a scaly centre. The eruption is characteristically localized to the upper trunk and the arms, but may also be restricted to the extremities or the neck. Involvement of the face is rare. The eruption tends to subside spontaneously within 4-6 weeks without leaving any marks. One attack leads to a life-long immunity. Second attacks are rare. This disease behaves like an exanthem but the causative agent has not so far been established.