Treatment
Treatment with emollients is used to relieve symptoms of cracking and dryness. Application of lubricants under plastic occlusion before bedtime appears to aid removal of scales on hands and feet. Other topical options include: topical corticosteroids alone, or combined with keratolytics, such as urea and vitamin D3 analogues. The most effective therapy is long term use of oral retinoids, such as acitretin and isotretinoin. Other effective systemic approaches include: methotrexate, cyclosporin and corticosteroids. There are also reports that the monoclonal antibody ustekinumab (which blocks IL-23/ IL-12) may be effective. See also
List of cutaneous conditions

Footnotes
Further reading
Dr. Griffith (June 1998). "Pityriasis rubra pilaris". In Champion R.H.; Burton J.L. ; Burns D.A. ; Breathnach S.M. (eds.). Textbook of Dermatology. Vol. 2 (6th ed.). pp. 1539–1545. ISBN 0-632-05064-0. == External links ==
Pulmonary alveolar microlithiasis (PAM) is a rare, inherited disorder of lung phosphate balance that is associated with small stone formation in the airspaces of the lung. Mutations in the gene SLC34A2 result in loss of a key sodium, phosphate co-transporter (called Npt2b), known to be expressed in distal alveolar type II cells, as well as in the mammary gland, and to a lesser extent in intestine, kidney, skin, prostate and testes. As the disease progresses, the lung fields become progressively more dense (white) on the chest xray, and low oxygen level, lung inflammation and fibrosis, elevated pressures in the lung blood vessels, and respiratory failure ensue, usually in middle age. The clinical course of PAM can be highly variable, with some patients remaining asymptomatic for decades, and others progressing more rapidly. There is no effective treatment, and the mechanisms of stone formation, inflammation and scarring are not known. Signs and symptoms
Patients typically have no symptoms until the third or fourth decade of life. In most cases, the disease is discovered incidentally on routine chest Xray. The most common symptoms include the following:
dyspnea
dry cough
chest pain
sporadic hemoptysis
asthenia
pneumothoraces

Genetics
PAM is hereditary and another involved family member can be identified in 36% to 61% of cases. Impaired activity of the SLC34A2 gene is responsible for PAM.The SLC34A2 gene encodes a membrane protein that is expressed primarily in the apical portions of alveolar type II cells and is the most abundant phosphate carrier in the lungs.