Relation to other rare genetic disorders
Recent findings in genetic research have suggested that a large number of genetic disorders, both genetic syndromes and genetic diseases, that were not previously identified in the medical literature as related, may be, in fact, highly related in the genetypical root cause of the widely varying, phenotypically-observed disorders. Thus, PCD is a ciliopathy. Other known ciliopathies include Bardet–Biedl syndrome, polycystic kidney and liver disease, nephronophthisis, Alström syndrome, Meckel–Gruber syndrome and some forms of retinal degeneration. Diagnosis
Several diagnostic tests for this condition have been proposed. These include nasal nitric oxide levels as a screening test, light microscopy of biopsies for ciliary beat pattern and frequency and electron microscopic examination of dynein arms, as the definite diagnosis method. Genetic testing has also been proposed but this is difficult given that there are multiple genes involved. Classification
When accompanied by the combination of situs inversus (reversal of the internal organs), chronic sinusitis, and bronchiectasis, it is known as Kartagener syndrome (only 50% of primary ciliary dyskinesia cases include situs inversus). Treatment
There are no standardized effective treatment strategies for the condition. Current therapies for PCD are extrapolated from Cystic Fibrosis and patients with non-CF bronchiectasis and lack validation for PCD-specific use. Severe fatal respiratory failure can develop; long-term treatment with macrolides such as clarithromycin, erythromycin and azithromycin has been empirically applied for the treatment of primary ciliary dyskinesia in Japan, though controversial due to the effects of the medications. Prognosis
There is no reliable estimate of life expectancy for people with PCD.
Several treatments including Promiseb, lactamide MEA gel, hydrocortisone 1% lotion, licochalcone 0.025%, flumethasone pivalate 0.02% ointment, and eosin 2% aqueous solution have been studied, however there is uncertainty regarding the efficacy and safety of these treatments.For adults: see the article on seborrheic dermatitis (the adult version of cradle cap). Scalp, behind ears, eyebrows
If the cradle cap is not severe, it could simply be combed out gently after bathing. The softened scales can then be brushed away with a soft brush, comb or cloth, but if not done very gently, this could worsen the condition and bring about temporary hair loss. Applying petroleum jelly (e.g., Vaseline) liberally overnight is another popular treatment. The softened scales either fall off during the night, or can be brushed off in the morning.There is broad disagreement regarding the role of shampoos. Some sources warn against frequent shampooing, others recommend it. Mild baby shampoo is often recommended, but the exact denotation of the label "mild" in this context is not quite clear. Baby shampoos often contain detergent surfactants, perfumes, quaternium-15 and other eczemagenic irritants. No studies have been performed on non-prescription shampoos.In stubborn cases some doctors may recommend keratolytic (dandruff) shampoos (e.g. with sulfur, selenium, zinc pyrithione, or salicylic acid) while others warn against the use of medicated shampoos in newborns due to systemic absorption. Dandruff shampoos often contain sodium dodecyl sulfate, a noted skin irritant.Steroid and tar preparations have also been used but may have drawbacks. The immunomodulators tacrolimus/Protopic and pimecrolimus/Elidel have not been approved for children under two years.