Medical Care
No disease-modifying therapy is available for Kearns-Sayre syndrome (KSS). Management is supportive vigilance for detection of associated problems. In the future, potential treatment in patients with Kearns-Sayre syndrome may attempt to inhibit mutant mtDNA replication or encourage replication of wild-type mtDNA. [29]
Surgical Care
In patients with aponeurogenic ptosis, surgical shortening of levator muscles can elevate the eyelid mechanically, but exposure may lead to corneal damage. Surgery to correct ptosis should occur only in centers with specialists in ophthalmic surgical procedures. [30, 31]
Surgical management of cricopharyngeal achalasia (incomplete opening of the upper oesophageal sphincter) may be needed if significant dysphagia is present. [32] Gastrostomy insertion is also an option.
The use of cochlear implants for patients with significant deafness is under investigation. [33]
The aforementioned study by Imamura et al, which involved a case report and literature review, indicated that pacemaker implantation may not by itself be effective enough in curbing sudden death in patients with arrhythmia-associated Kearns-Sayre syndrome, with the investigators recommending implantable cardioverter defibrillators as a means of combatting mortality. They suggested that, while early afterdepolarizations (EADs) linked to bradycardia-associated QT prolongation may be suppressed via pacemakers, delayed afterdepolarizations may produce VA even in the presence of EAD suppression. [22]
Consultations
All patients with Kearns-Sayre syndrome require the care of an ophthalmologist. [34] Consult with a cardiologist regarding pacemaker insertion for heart block. Additional consultations (eg, endocrinologist, neurologist, psychiatrist, neuropsychologist) may be needed, based on the status of the patient and the presence of complications. Genetic counselling is also indicated.
Diet
Supplementation with coenzyme Q10 may be indicated. Supplementation with folinic acid led to clinical and radiological improvement in a child with incomplete Kearns-Sayre syndrome, cerebral folate deficiency, and leukoencephalopathy. [35]
Activity
Exercise may help patients with myopathy. Exercise that causes concentric shortening of muscles leads to proliferation of satellite cells, the muscle cell precursors that also are involved in muscle regeneration. Satellite cells contain undetectable levels of mutant mtDNA; if they proliferate, the proportion of wild-type DNA to mutant mtDNA can beneficially increase. [36] Exercising to this extent is difficult for severely affected or young patients.
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Skeletal muscle stained for both cytochrome oxidase (COX) and succinic dehydrogenase (SDH), two mitochondrial respiratory chain enzymes. Fibers that stain only for SDH and are COX-negative appear blue. Original magnification X 50.
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Bilateral ptosis and external ophthalmoplegia. Top: patient looking straight ahead. Below: patient is being asked to look in the direction of the arrow in each case. Restriction of eye movements in each direction is demonstrated.
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Modified Gomori Trichrome stain showing ragged red fibres. These show red staining round the periphery as well as within the sarcoplasm, giving a speckled appearance. Of the two affected muscle fibres pictured here, the one on the right shows a more extreme degree of mitochondrial proliferation and also some degeneration/vacuolation than the one on the left.
