King-Denborough Syndrome: report of two Brazilian cases

Abstract

-We report on two boys aged 2 and 6 years-old respectively with dysmorphic face, ptosis, downslanting palpebral fissures, hypertelorism, epicanthic folds, low-set ears, malar hypoplasia, micrognathia, high-arched palate, clinodactyly, palmar simian line, pectus excavatum, winging of the scapulae, lumbar lordosis and mild thoracic scoliosis who present congenital hypotonia, slightly delayed motor development, diffuse joint hyperextensibility and mild proximal weakness. The muscle biopsy revealed minimal but identifiable changes represented by size fiber variability, type I fiber predominance and atrophy, perimysial fibrous infiltration and some disarray of the intermyofibrillary network. These cases correspond to the first Brazilian reports of the King-Denborough syndrome and our objective is increasing the awareness of this disorder as these patients are predisposed to developing malignant hyperthermia.KEY WORDS: King-Denborough syndrome, congenital myopathy, malignant hyperthermia. Síndrome de King-Denborough: relato de dois casosRESUMO -Relatamos dois meninos de 2 e 6 anos de idade que apresentam aspectos dismórficos caracterizados por facies alongada, ptose e fenda palpebral anti-mongólica, hipertelorismo, epicanto bilateral, orelhas de implantação baixa, hipoplasia malar, micrognatia, pálato ogival, clinodactilia, prega palmar única, "pectus excavatum", escápulas aladas, lordose lombar e escoliose torácica. Apresentam hipotonia congênita, hiperextensibilidade articular, fraqueza muscular e retardo do desenvolvimento motor. A biópsia muscular revelou em ambos alterações mínimas: variabilidade do tamanho das fibras, predomínio e atrofia de fibras tipo I, discreta infiltração perimisial e desarranjo intermiofibrilar. Os aspectos dismórficos associados à miopatia congênita configuram a síndrome de King-Denborough, da qual acreditamos serem estes os primeiros casos descritos no Brasil. Como a síndrome se acompanha de alto risco de desenvolver hipertermia maligna na indução anestésica, o objetivo deste relato é chamar a atenção para a necessidade do diagnóstico pré-operatório, a fim de evitar esta gravíssima intercorrência. PALAVRAS-CHAVE: síndrome de King-Denborough, miopatia congênita, hipertermia maligna.

Central Core Disease: Atypical Case With Respiratory Insufficiency in an Intensive Care Unit

“…However, this syndrome is characterized by a dysmorphic face, ptosis, down-slanting palpebral fissures, hypertelorism, epicanthic folds, lowset ears, malar hypoplasia, micrognathia, a high-arched palate, clinodactyly, a palmar simian line, pectus excavatum, winging of the scapulae, and diffuse joint hyperextensibility. 12,13 The presented case had kyphoscoliosis for 1 year, although muscle weakness was not significant. Moderate limitation of movements of hip or knee joints owing to muscle contractures is also reported in patients with central core disease.…”

“…14,15 These biopsy findings are also sufficient to differentiate it from King-Denborough syndrome, muscle biopsy of which demonstrates fiber size variability, type 1 fiber predominance, and atrophy. 12 Typical presentation of central core disease is characterized by hypotonia and motor developmental delay in infancy, varying degrees of symmetric proximal muscle weakness, and wasting. 6,10 However, adult onset of disease and progression has also been reported.…”

Malignant hyperthermia in a 4-year-old girl during anesthesia induction with sevoflurane and succinylcholine for congenital ptosis surgery

“…King-Denborough syndrome is known to predispose to MH. Although the cause of King-Denborough syndrome is not fully understood, some cases have been attributed to RYR1 gene [26], [27]…”

Delayed Onset Malignant Hyperthermia after Sevoflurane

“…Reed et al have emphasized the fact that patients with King Denborough syndrome may undergo general anesthesia for cryptrochidism and skeletal deformities and the objective must be increasing the awareness of this disorder as these patients are predisposed to developing malignant hyperthermia [7]. …”