Gilles Roger

Loss-of-function mutations in a human gene related to Chlamydomonas reinhardtii dynein IC78 result in primary ciliary dyskinesia.

Primary ciliary dyskinesia (PCD) is a group of heterogeneous disorders of unknown origin, usually inherited as an autosomal recessive trait. Its phenotype is characterized by axonemal abnormalities of respiratory cilia and sperm tails leading to bronchiectasis and sinusitis, which are sometimes associated with situs inversus (Kartagener syndrome) and male sterility. The main ciliary defect in PCD is an absence of dynein arms. We have isolated the first gene involved in PCD, using a candidate-gene approach developed on the basis of documented abnormalities of immotile strains of Chlamydomonas reinhardtii, which carry axonemal ultrastructural defects reminiscent of PCD. Taking advantage of the evolutionary conservation of genes encoding axonemal proteins, we have isolated a human sequence (DNAI1) related to IC78, a C. reinhardtii gene encoding a dynein intermediate chain in which mutations are associated with the absence of outer dynein arms. DNAI1 is highly expressed in trachea and testis and is composed of 20 exons located at 9p13-p21. Two loss-of-function mutations of DNAI1 have been identified in a patient with PCD characterized by immotile respiratory cilia lacking outer dynein arms. In addition, we excluded linkage between this gene and similar PCD phenotypes in five other affected families, providing a clear demonstration of locus heterogeneity. These data reveal the critical role of DNAI1 in the development of human axonemal structures and open up new means for identification of additional genes involved in related developmental defects.

RPGR is mutated in patients with a complex X linked phenotype combining primary ciliary dyskinesia and retinitis pigmentosa.

Introduction: Primary ciliary dyskinesia (PCD) is a rare disease classically transmitted as an autosomal recessive trait and characterised by recurrent airway infections due to abnormal ciliary structure and function. To date, only two autosomal genes, DNAI1 and DNAH5 encoding axonemal dynein chains, have been shown to cause PCD with defective outer dynein arms. Here, we investigated one non-consanguineous family in which a woman with retinitis pigmentosa (RP) gave birth to two boys with a complex phenotype combining PCD, discovered in early childhood and characterised by partial dynein arm defects, and RP that occurred secondarily. The family history prompted us to search for an X linked gene that could account for both conditions. Results: We found perfect segregation of the disease phenotype with RP3 associated markers (Xp21.1). Analysis of the retinitis pigmentosa GTPase regulator gene (RPGR) located at this locus revealed a mutation (631_IVS6+9del) in the two boys and their mother. As shown by study of RPGR transcripts expressed in nasal epithelial cells, this intragenic deletion, which leads to activation of a cryptic donor splice site, predicts a severely truncated protein. Conclusion: These data provide the first clear demonstration of X linked transmission of PCD. This unusual mode of inheritance of PCD in patients with particular phenotypic features (that is, partial dynein arm defects and association with RP), which should modify the current management of families affected by PCD or RP, unveils the importance of RPGR in the proper development of both respiratory ciliary structures and connecting cilia of photoreceptors.

CCDC39 is required for assembly of inner dynein arms and the dynein regulatory complex and for normal ciliary motility in humans and dogs

Primary ciliary dyskinesia (PCD) is an inherited disorder characterized by recurrent infections of the upper and lower respiratory tract, reduced fertility in males and situs inversus in about 50% of affected individuals (Kartagener syndrome). It is caused by motility defects in the respiratory cilia that are responsible for airway clearance, the flagella that propel sperm cells and the nodal monocilia that determine left-right asymmetry. Recessive mutations that cause PCD have been identified in genes encoding components of the outer dynein arms, radial spokes and cytoplasmic pre-assembly factors of axonemal dyneins, but these mutations account for only about 50% of cases of PCD. We exploited the unique properties of dog populations to positionally clone a new PCD gene, CCDC39. We found that loss-of-function mutations in the human ortholog underlie a substantial fraction of PCD cases with axonemal disorganization and abnormal ciliary beating. Functional analyses indicated that CCDC39 localizes to ciliary axonemes and is essential for assembly of inner dynein arms and the dynein regulatory complex.

Severe laryngomalacia: surgical indications and results in 115 patients.

Between 1987 and 1993, 115 children were operated on for severe forms of laryngomalacia in two pediatric ear, nose, and throat (ENT) departments. The criteria used to determine the severity of the illness were selected following short hospitalization periods during which the children received both pediatric and ENT checkups. Based on clinical manifestations and/or the results of pH monitoring gastroesophageal reflux was found to be present in 68% of the children in the study. Detailed analysis and endoscopy were used to differentiate the symptoms that were related to laryngomalacia from those that were caused by other conditions, including mixed‐breathing, swallowing, and sucking difficulties.

The Biology and Management of Subglottic Hemangioma: Past, Present, Future†

Objectives/Hypothesis: Objectives were 1) to review the presentation, natural history, and management of subglottic hemangioma; 2) to assess the affect of five variables (age, gender, degree of subglottic narrowing, location and extent of subglottic hemangioma, and lack or presence of other hemangioma) and the outcome of six different treatment modalities (conservative monitoring, corticosteroid, laser surgery, tracheotomy, laryngotracheoplasty, and interferon) in the management of subglottic hemangioma; and 3) to present specific guidelines to help determine the best possible treatment modality at the time of initial presentation.

22q11.2 duplication syndrome: two new familial cases with some overlapping features with DiGeorge/velocardiofacial syndromes.

Twenty‐one patients, including our two cases, with variable clinical phenotype, ranging from mild learning disability to severe congenital malformations or overlapping features with DiGeorge/velocardiofacial syndromes (DG/VCFS), have been shown to have a chromosome duplication 22q11 of the region that is deleted in patients with DG/VCFS. The reported cases have been identified primarily by interphase FISH and could have escaped identification and been missed by routine cytogenetic analysis. Here we report on two inherited cases, referred to us, to rule out 22q11 microdeletion diagnosis of VCFS. The first patient was a 2‐month‐old girl, who presented with cleft palate, minor dysmorphic features including short palpebral fissures, widely spaced eyes, long fingers, and hearing loss. Her affected mother had mild mental retardation and learning disabilities. The second patient was a 7½‐year‐old boy with velopharyngeal insufficiency and mild developmental delay. He had a left preauricular tag, bifida uvula, bilateral fifth finger clinodactyly, and bilateral cryptorchidism. His facial features appeared mildly dysmorphic with hypertelorism, large nose, and micro/retrognathia. The affected father had mild mental retardation and had similar facial features. FISH analysis of interphase cells showed three TUPLE1‐probe signals with two chromosome‐specific identification probes in each cell. FISH analysis did not show the duplication on the initial testing of metaphase chromosomes. On review, band q11.2 was brighter on one chromosome 22 in some metaphase spreads. The paucity of reported cases of 22q11.2 microduplication likely reflects a combination of phenotypic diversity and the difficulty of diagnosis by FISH analysis on metaphase spreads. These findings illustrate the importance of scanning interphase nuclei when performing FISH analysis for any of the genomic disorders.

Nasal dermoid sinus cysts in children

Thirty‐six children with nasal dermoid sinus cysts were treated in the Department Pediatric Otolaryngology, Armand Trousseaus Childrens Hospital (Paris, France) between 1974 and 1994. Ten of the patients presented with a midline cyst only, eight had nasal pits only, and 18 had combined cases. In six of the 36 patients, presurgical imagery indicated signs of intracranial extension of the tract, reaching the foramen caecum without intracranial mass. Three surgical techniques were used: an external rhinoplasty approach with medial crura section in 23 cases, a direct median approach in seven cases, and a paracanthal approach in six cases. Only two cases had meningeal adherences. Two superficial recurrences occurred within the 7‐year follow‐up period. Widening of the scar occurred in four children after verticomedian approach or nasal pit excision. The external rhinoplasty procedure with medial crura section results in a wide surgical approach, low recurrence rate, and good aesthetic results.

Myringoplasty in Children: Predictive Factors of Outcome

Objectives: To assess the results of myringoplasty in children and to determine which factors independently influence the postoperative results. Study Design: Retrospective study of the anatomic and functional results of 231 consecutive myringoplasties performed in 188 children between 1988 and 1992. Multivariate analysis of poor prognostic factors by cross‐sectional comparison 1 year after surgery. Methods: Myringoplasties were performed via an endaural approach with a fascia temporalis underlay graft. Results: In 216 of 231 ears (93.5%) the tympanic membrane was closed. A good anatomic outcome was considered to have been achieved in 188 ears (81.6%), although in 18 ears (7.8%) seromucous otitis media occurred, in 8 ears (3.5%) a progressive retraction pocket was encountered, and in 2 ears significant lateralization was present. One hundred thirty‐nine (67.5%) of the 206 ears tested in the postoperative period had a postoperative air‐bone gap of 10 dB or less. On average, mean bone conduction remained unaltered. The age of the patient and the size and the location of the perforation did not affect the outcome. Three prognostic factors for an abnormal postoperative tympanic membrane were found, with 95% confidence intervals: inflammatory changes in the middle ear mucosa (P < .05), contralateral tympanic perforation (P < .05), and contralateral cholesteatoma (P < .01). Conclusions: Myringoplasty with underlay grafting of the fascia temporalis in children gives good anatomic and functional results. Inflammatory changes within the middle ear mucosa, contralateral tympanic perforation, and contralateral cholesteatoma independently influence the risk of an abnormal postoperative tympanic membrane. The presence of one of these factors preoperatively should lead to the consideration of alternative, more durable graft material, such as autologous cartilage.

Medical and surgical complications in pediatric cochlear implantation.

OBJECTIVES To report complications of cochlear implantation (CI) in children and to analyze risk factors. DESIGN Retrospective study from January 1, 1990, through April 30, 2008, with a mean follow-up of 5.5 years (range, 1 month to 17 years). SETTING Tertiary academic center. PATIENTS Four hundred thirty-four patients younger than 16 years. Mean age at CI was 4.7 (range, 0.6-16.0) years. Forty-one children (9.4%) underwent CI when younger than 24 months. Forty-three (9.9%) had inner ear malformations. MAIN OUTCOME MEASURES Complications after CI, classified into early (0-8 days) or delayed (>8 days) and major or minor. Spontaneous failures of internal devices were excluded. Correlation to age at CI, local trauma, and inner ear malformations were analyzed using the chi(2) test. RESULTS Forty-three patients (9.9%) experienced complications. Delayed complications occurred in 28 patients (65.1%), with a mean delay of 2.2 (range, 0.1-8.4) years. Twenty-four patients (5.5%) had major complications, consisting of severe cutaneous infections (15 patients), magnet displacement (3), meningitis (2), cholesteatoma (2), cerebrospinal fluid leak (1), and electrode misplacement (1). Nineteen (4.4%) had minor complications, consisting of vertigo (9 patients), soft-tissue infection (5), persistent otitis media (4), and facial palsy (1). Complications led to reimplantation in 13 of the 43 patients (30.2%). Trauma to the mastoid area (14 patients) and inner ear malformations (51) were highly correlated with major delayed complications (P < .001) and early minor complications (P < .001), respectively. Young age at CI was not correlated with any type of complication. CONCLUSIONS Complications of CI in children are common, with trauma as a major factor. Inner ear malformations should prompt specific preventive management. Cochlear implantation in young children did not appear to be a risk factor in this study.

Cochlear implantation in children with internal ear malformations.

Objective: To evaluate surgical aspects and results of cochlear implantation in inner ear malformations. Study Design: Retrospective cohort study. Setting: Ear, nose, and throat department of a tertiary referral hospital. Patients: Out of 260 implanted children, 18 (6.9%) had inner ear malformations: complex cochleovestibular malformation (n = 11), common cavity (n = 1), and enlarged vestibular aqueduct (EVA) (n = 6). Deafness was progressive in 12 cases (G1) and congenital in 6 cases (G2). Genetics lead to diagnosis in 12 of 13 cases: PSD mutation (n = 11), Waardenburg syndrome (n = 1), negative (1). Mean age at implant was 7.8 years. Mean follow-up period was 48 months. Main Outcome Measures: Medical and surgical outcomes were reported. Closed (CSW) and open (OSW) set word perception and level of speech production were evaluated each year. The results were compared pre- and postoperatively and between the two groups. Results: Gusher at surgery was observed in 50% of cases, with a persistent leak in one case. No facial injury or infectious complications were observed. At 12 months, 83% of the population had achieved more than 75% recognition in CSW, versus 16% before implant (p = 0.001). After 2 years, 64% of patients had more than 50% recognition in OSW. Good oral language was seen in 76% at 2 years and 100% at 3 years, versus 55% before implant (respectively, p > 0.05 and p = 0.03). At 1 year after implant, 83% of the G1 and 20% of the G2 achieved more than 50% recognition in OSW (p = 0.02). After 24 months, 83% of G1 and 40% of G2 had more than 50% in OSW (p > 0.05). Before implant, 75% in G1 and 0% in G2 had good oral language (p = 0.01). At 1 year, 83% in G1 and 16% in G2 had good oral language (p = 0.02). At 2 years, 100% in G1 and 20% in G2 had good oral language (p = 0.02). One child in G1 had no improvement after implantation. Conclusions: No major complication was seen. Perceptive and linguistic results were variable and depended on the type of the deafness. In progressive deafness, the perceptive and linguistic result are expected to be good. In congenital deafness, the results are more variable.