Identification of mutations in the AIPL1, CRB1, GUCY2D, RPE65, and RPGRIP1 genes in patients with juvenile retinitis pigmentosa

OBJECTIVE

To identify mutations in the AIPL1, CRB1, GUCY2D, RPE65, and RPGRIP1 genes in patients with juvenile retinitis pigmentosa.

METHODS

Mutation analysis was carried out in a group of 35 unrelated patients with juvenile autosomal recessive retinitis pigmentosa (ARRP), Leber's congenital amaurosis (LCA), or juvenile isolated retinitis pigmentosa (IRP), by denaturing high performance liquid chromatography followed by direct sequencing.

RESULTS

All three groups of patients showed typical combinations of eye signs associated with retinitis pigmentosa: pale optic discs, narrow arterioles, pigmentary changes, and nystagmus. Mutations were found in 34% of

PATIENTS

in CRB1 (11%), GUCY2D (11%), RPE65 (6%), and RPGRIP1 (6%). Nine mutations are reported, including a new combination of two mutations in CRB1, and new mutations in GUCY2D and RPGRIP1. The new GUCY2D mutation (c.3283delC, p.Pro1069ArgfsX37) is the first pathological sequence change reported in the intracellular C-terminal domain of GUCY2D, and did not lead to the commonly associated LCA, but to a juvenile retinitis pigmentosa phenotype. The polymorphic nature of three previously described (pathological) sequence changes in AIPL1, CRB1, and RPGRIP1 was established. Seven new polymorphic changes, useful for further association studies, were found.

CONCLUSIONS

New and previously described sequence changes were detected in retinitis pigmentosa in CRB1, GUCY2D, and RPGRIP1; and in LCA patients in CRB1, GUCY2D, and RPE65. These data, combined with previous reports, suggest that LCA and juvenile ARRP are closely related and belong to a continuous spectrum of juvenile retinitis pigmentosa.

Deletions involving long-range conserved nongenic sequences upstream and downstream of FOXL2 as a novel disease-causing mechanism in blepharophimosis syndrome

The expression of a gene requires not only a normal coding sequence but also intact regulatory regions, which can be located at large distances from the target genes, as demonstrated for an increasing number of developmental genes. In previous mutation studies of the role of FOXL2 in blepharophimosis syndrome (BPES), we identified intragenic mutations in 70% of our patients. Three translocation breakpoints upstream of FOXL2 in patients with BPES suggested a position effect. Here, we identified novel microdeletions outside of FOXL2 in cases of sporadic and familial BPES. Specifically, four rearrangements, with an overlap of 126 kb, are located 230 kb upstream of FOXL2, telomeric to the reported translocation breakpoints. Moreover, the shortest region of deletion overlap (SRO) contains several conserved nongenic sequences (CNGs) harboring putative transcription-factor binding sites and representing potential long-range cis-regulatory elements. Interestingly, the human region orthologous to the 12-kb sequence deleted in the polled intersex syndrome in goat, which is an animal model for BPES, is contained in this SRO, providing evidence of human-goat conservation of FOXL2 expression and of the mutational mechanism. Surprisingly, in a fifth family with BPES, one rearrangement was found downstream of FOXL2. In addition, we report nine novel rearrangements encompassing FOXL2 that range from partial gene deletions to submicroscopic deletions. Overall, genomic rearrangements encompassing or outside of FOXL2 account for 16% of all molecular defects found in our families with BPES. In summary, this is the first report of extragenic deletions in BPES, providing further evidence of potential long-range cis-regulatory elements regulating FOXL2 expression. It contributes to the enlarging group of developmental diseases caused by defective distant regulation of gene expression. Finally, we demonstrate that CNGs are candidate regions for genomic rearrangements in developmental genes.

Psammomatoid ossifying fibroma of the ethmoid

We present a 16 year-old girl who suffered since one year of a painless slow growing mass on the left medial orbital rim causing globe displacement. CT-scan and MRI of the orbit with T1 and T2 weighted images showed the presence of a large mucocoele in the frontal sinus. This occurred secondary to the obstruction of the sinonasal tract by a bony tumour. Histopathology showed a lesion consisting of fibrous tissue and ossicles or psammomatoid bodies. The diagnosis of a psammomatoid ossifying fibroma (POF) was made.

Orbital lymphangioma: clinical features and management

PURPOSE

To report 5 cases of orbital lymphangioma.

METHODS

All patients underwent ophthalmological, clinical and neuroradiological evaluation.

RESULTS

At presentation all patients (4 children and one adult patient) had unilateral proptosis. Restricted eye movement was present in 3 patients, ptosis and amblyopia in 2. Compressive optic neuropathy with visual loss was noticed in one patient. Palatal localization was found in 2 patients, maxillofacial localization in one. Associated intracranial vascular anomaly was present in one patient. Three patients who underwent surgery, developed recurrences. No regression of lymphangioma was noticed nor with Interferon, nor with steroids.

CONCLUSION

Lymphangioma has to be included in the differential diagnosis of childhood proptosis. Extraorbital localization, under which associated intracranial developmental venous vascular anomaly, has to be searched for. In most of the cases conservative treatment is mandatory.

Corneal decompensation in a boy with Kearns-Sayre syndrome

This paper describes the clinical history of a young boy with Kearns-Sayre syndrome. The first presenting symptom of Kearns-Sayre syndrome in this boy was corneal edema with photophobia and tearing.

Symptomatic pineal cysts: clinical manifestations and management

Between 1991 and 2000, seven patients presented with symptomatic pineal cysts at our hospital (6 females, 1 male). Average age was 22 years (range 4-33 years). Headache was present in 6 patients, who were subsequently operated on. A scotoma and a transient inferior visual field deficit were minor signs in two patients respectively. A Parinaud syndrome with vertical gaze paralysis was found in none. In one child, paroxysmal pupillary dilatations and contractions ('springing pupils') constituted the only signs and a conservative policy was adopted. Four patients presented with hydrocephalus and were treated by an endoscopic resection of their pineal cysts (one stereotactically, three free-hand). Two other patients presented with a prolonged history of symptoms and signs: headache alone in one, headache with discrete neurological deficits in the other. Ventricles in these two patients were not dilated and therefore an open cyst resection by infratentorial supracerebellar approach was performed. Average follow-up in the six "operated" patients was 29 months (range 12-108 months). All four patients treated by endoscopy, are symptom-free at follow-up, whereas the two who were approached by open surgery, are not. Clinical presentation, radiological evaluation and treatment modalities of pineal cysts are discussed and compared with experiences reported in the literature. It is concluded that pineal cysts in the presence of obstructive hydrocephalus are a clear indication for endoscopy with a rigid endoscope.

Spectrum of FOXL2 gene mutations in blepharophimosis-ptosis-epicanthus inversus (BPES) families demonstrates a genotype--phenotype correlation

Mutations in FOXL2, a forkhead transcription factor gene, have recently been shown to cause blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) types I and II, a rare genetic disorder. In BPES type I a complex eyelid malformation is associated with premature ovarian failure (POF), whereas in BPES type II the eyelid defect occurs as an isolated entity. In this study, we describe the identification of novel mutations in the FOXL2 gene in BPES types I and II families, in sporadic BPES patients, and in BPES families where the type could not be established. In 67% of the patients studied, we identified a mutation in the FOXL2 gene. In total, 21 mutations (17 of which are novel) and one microdeletion were identified. Thirteen of these FOXL2 mutations are unique. In this study, we demonstrate that there is a genotype--phenotype correlation for either types of BPES by the finding that mutations predicted to result in a truncated protein either lacking or containing the forkhead domain lead to BPES type I. In contrast, duplications within or downstream of the forkhead domain, and a frameshift downstream of them, all predicted to result in an extended protein, cause BPES type II. In addition, in 30 unrelated patients with isolated POF no causal mutations were identified in FOXL2. Our study provides further evidence that FOXL2 haploinsufficiency may cause BPES types I and II by the effect of a null allele and a hypomorphic allele, respectively. Furthermore, we propose that in a fraction of the BPES patients the genetic defect does not reside within the coding region of the FOXL2 gene and may be caused by a position effect.

Imaging studies in the diagnostic workup of neonatal nasal obstruction

Twelve neonates presenting with nasal obstruction after birth were evaluated by imaging studies for diagnostic reasons. Four groups were recognized: Group I: choanal atresia (n = 5) and choanal stenosis (n = 1); Group II: congenital nasal pyriform aperture stenosis (CNPAS) (n = 3) and holoprosencephaly (n = 1); Group III: nasolacrimal duct mucocele (n = 1); Group IV: nasal hypoplasia (n = 1). Associated anomalies were found in eight patients. Four patients with choanal atresia showed manifestations of the CHARGE (coloboma, congenital heart defect, atretic choanae, retarded physical and neuromotor development associated with central nervous system anomalies, genital hypoplasia, and ear anomaly and/or deafness) association. In the fifth patient with choanal atresia, the diagnosis of amnion disruption sequence was made. One patient with CNPAS had a solitary maxillary central incisor (SMCI), a mild form of holoprosencephaly. Besides proboscis and synophthalmos, SMCI was also present in the holoprosencephaly case. The patient with severe nasal hypoplasia had warfarin embryopathy. This review emphasizes the need for performing imaging studies in the diagnostic workup of neonates born with nasal obstruction.

A new mitochondrial point mutation in the transfer RNA(Leu) gene in a patient with a clinical phenotype resembling Kearns-Sayre syndrome

OBJECTIVE

To report on the molecular identification of a novel heteroplasmic G-to-A transition at mitochondrial DNA position 3249 in transfer RNA(Leu) gene in a patient with a clinical phenotype resembling Kearns-Sayre syndrome.

PATIENT AND METHODS

A 34-year-old patient had been suffering for more than 10 years from progressive visual failure, neurosensorial hearing loss, exercise intolerance, muscle weakness, paresthesia in the lower limbs, and difficulties swallowing. Clinical examination revealed generalized muscle wasting, ptosis, external ophthalmoplegia, and ataxia. Ophthalmologic examination showed dystrophic features in the cornea and retina. In skeletal muscle, morphologic and biochemical studies of the respiratory chain complexes were performed. Polymerase chain reaction, single-strand conformation polymorphism, and direct sequencing were used to screen for mutations in the 22 mitochondrial transfer RNA genes.

RESULTS

In skeletal muscle, a significantly decreased catalytic activity of complex I was detected by spectrophotometric analysis and numerous cytochrome c oxidase-negative ragged-red fibers were seen on morphologic examination. A G-to-A substitution 3249 (G3249A) mutation was found in the transfer RNA(Leu) gene of the patient and mutant mitochondrial DNA represented 85% of the total in skeletal muscle but only 45% in leukocytes. The mutation was shown to be present in a small fraction in leukocytes from the unaffected mother and to be absent in leukocytes from the healthy sister.

CONCLUSIONS

A causal relationship between a heteroplasmic G3249A transfer RNA(Leu) mutation in a patient suffering from progressive external ophthalmoplegia, retinal dystrophy, ataxia, neurosensorial hearing loss, and muscle wasting is postulated. To our knowledge, the G3249A mutation has never previously been described and was not detected in control subjects.

Homozygous and compound-heterozygous type I plasminogen deficiency is a common cause of ligneous conjunctivitis

Severe type I plasminogen deficiency has been recently linked to ligneous conjunctivitis, a rare and uncommon form of chronic conjunctivitis. In this study, eight unrelated ligneous conjunctivitis patients living in different parts of the world were examined. All affected subjects from which plasma was available displayed absent or markedly reduced plasminogen antigen and plasminogen functional activity. Molecular genetic studies of seven patients identified a Lys19-->Glu mutation in two boys in a homozygous state, and in two girls in a compound-heterozygous state in which the second plasminogen gene carried a missense (Arg134-->Lys) and a nonsense mutation (Cys133--> Stop), respectively. A fifth patient was shown to be homozygous for a frameshift mutation in plasminogen exon 14 (Gly565ins-G). In two unrelated subjects with ligneous conjunctivitis no mutations in the plasminogen gene were identified. Our results suggest that the Lys19-->Glu mutation is the most prevalent mutation in the plasminogen gene of patients with ligneous conjunctivitis.

Mitochondrial mutations of Leber's hereditary optic neuropathy: a risk factor for multiple sclerosis

Multiple sclerosis (MS) and Leber's hereditary optic neuropathy (LHON) have been found to occur in combination. Based on an extensive literature search and on a clinical analysis of 55 LHON pedigrees (103 patients) and 40 patients with definite MS, this study concludes that the association of LHON and MS is more than a coincidence, and that carrying a primary LHON mutation is a risk factor for developing MS. All three primary LHON mutations occurring in the European and North American populations have been found to be associated with an MS-like syndrome. The neurological characteristics of MS associated with LHON are indistinguishable from those of MS in general, but the severe and bilateral visual symptoms and signs justify considering these patients as a clinical subgroup of MS and screening them for LHON mutations. However, screening LHON patients for MS appears to be more rewarding.

Sorsby fundus dystrophy without a mutation in the TIMP-3 gene

AIMS

To examine a large family with an autosomal dominant fundus dystrophy and to investigate whether or not mutations in TIMP-3 gene were involved.

METHODS

A large family of 58 individuals with an autosomal dominant fundus dystrophy was examined ophthalmologically. A DNA linkage analysis in the 22q12.1-q13.2 region was performed. The TIMP-3 gene was screened for mutations in all five exons.

RESULTS

In this large family 15 individuals were affected. All other individuals were found to be clinically unaffected. Pisciform flecks in the midperiphery and drusen-like deposits were the most typical ophthalmological finding in this family and were encountered from the fifth decade on. Chorioretinal atrophy and neovascularisation with disciform lesions characterised the disease from the sixth decade on. Linkage analysis using an affected only analysis, showed a maximum positive lod score of 3.94 at theta = 0.0 with marker D22S283. No mutations possibly causing Sorsby fundus dystrophy were found in either the exonic sequences, the promotor region, or the 3'UTR.

CONCLUSION

The family in this pedigree has an autosomal dominant fundus dystrophy, which is most probably Sorsby fundus dystrophy. Although, in the linkage analysis, significant positive lod scores were found with the region 22q12.1-q13.2, no causative mutations could be identified in the TIMP-3 gene.

Missense mutations in the most ancient residues of the PAX6 paired domain underlie a spectrum of human congenital eye malformations

Mutations of the human PAX6 gene underlie aniridia (congenital absence of the iris), a rare dominant malformation of the eye. The spectrum of PAX6 mutations in aniridia patients is highly biased, with 92% of all reported mutations leading to premature truncation of the protein (nonsense, splicing, insertions and deletions) and just 2% leading to substitution of one amino acid by another (missense). The extraordinary conservation of the PAX6 protein at the amino acid level amongst vertebrates predicts that pathological missense mutations should in fact be common even though they are hardly ever seen in aniridia patients. This indicates that there is a heavy ascertainment bias in the selection of patients for PAX6 mutation analysis and that the 'missing' PAX6 missense mutations frequently may underlie phenotypes distinct from textbook aniridia. Here we present four novel PAX6 missense mutations, two in association with atypical phenotypes: ectopia pupillae (displaced pupils) and congenital nystagmus (searching gaze), and two in association with more recognizable aniridia phenotypes. Strikingly, all four mutations are located within the PAX6 paired domain and affect amino acids which are highly conserved in all known paired domain proteins. Our results support the hypothesis that the under-representation of missense mutations is caused by ascertainment bias and suggest that a substantial burden of PAX6 -related disease remains to be uncovered.

A puzzling case: conjunctivitis lignosa?

We describe the clinical history, histopathology and treatment of a two and a half year old boy. He presents with a chronic, unilateral and (pseudo) membranous conjunctivitis, preceded by ear-nose-throat problems and arthritis. The case was considered to be a ligneous conjunctivitis. Treatment consisted of repeated removal of the membranes, combined with topical hyaluronidase, alpha-chymotrypsin, cyclosporin, heparin and antibiotics, and was deceiving.

The Hermansky-Pudlak syndrome

The Hermansky-Pudlak syndrome (HPS) associates oculocutaneous albinism with a haemorrhagic diathesis and the accumulation of ceroid-like material in different tissues. HPS is not an uncommon type of albinism as it was diagnosed in 13.5% (8/59) of our autosomal recessive albinos. These eight patients were evaluated ophthalmologically and haematologically. Apart from the symptoms caused by the albinism, accompanying signs vary from ecchymoses to life threatening haemorrhages and death by associated restrictive lung disease. Recognition of this syndrome by the ophthalmologist can be of major importance in this serious and eventually fatal disorder.

The endoscopic approach for congenital nasolacrimal duct obstruction

Probing of the nasolacrimal duct is a common procedure in children with congenital stenosis. Although simple probing of the nasolacrimal duct is successful in a majority of patients, a number of failures occur. In those temporary intubation of the nasolacrimal duct with a silicone drain may solve the problem. We performed silicone intubation in 11 infants under nasal endoscopic control. By this improved visualization of the inferior meatus, the procedure was facilitated. In four children the probe was unable to pierce the nasal mucosa and stayed in the submucosal space. An incision of the nasal mucosa was needed before the probe could be passed into the nasal lumen. We believe that this situation, inability to pierce the nasal mucosa, may explain a number of failures of simple probing. It is therefore advisable, especially if initial probing has failed, to repeat the procedure under endoscopic control.

Fibrotic eye muscles, Axenfeld anomaly, flat face, and mild developmental retardation: a new example of the Chitty syndrome

We have studied a girl with fibrotic extrinsic eye muscles, Axenfeld anomaly, unusual facial appearance, mild hydrocephaly, and neurodevelopmental delay. Her condition is similar to the one described recently in members of a single family by Chitty et al. [1991, Am J Med Genet 40:417-420]. We suggest that she represents a second example of what may be called the Chitty syndrome.

Conclusive evidence for a distinct congenital stationary night blindness locus in Xp21.1

X linked congenital stationary night blindness (CSNBX) is a non-progressive retinal disorder characterised by decreased visual acuity and disturbance of night vision. CSNBX appears to be not only clinically but also genetically heterogeneous. On studying a single large family, we recently suggested the presence of a distinct locus for CSNBX in Xp21.1. Here, we describe the results of a linkage analysis in another large CSNBX family, which confirms this finding. Thus, the data presented here provide conclusive evidence for a distinct CSNBX locus in Xp21.1, closely linked to the X linked retinitis pigmentosa type 3 gene. The results combined with other published results indicate the order Xpter-DXS451-DMD-DYS1-(DXS1110, CSNBX1, XLRP3)-DXS7-(CSNBX2, XLRP2)-DXS14-Xcen.

Cohen syndrome: the clinical symptoms and stigmata at a young age

We present the clinical findings and follow-up data of four female children with Cohen syndrome, two sisters and one pair of dizygotic female twins. The most characteristic findings from birth on were as follows: 1. Low-normal growth parameters at birth. 2. Mild hypotonia and evidence of progressive microcephaly with narrow forehead in the first year of life. 3. Neutropenia was present from the beginning, remained unchanged over the years and is not associated with higher susceptibility to infections. 4. Autistic behavior and severe psychomotor retardation up to the age of 2 years. At that age the ocular anomalies with high-grade myopia and chorioretinal dystrophy were diagnosed. Correction of the myopia resulted in a marked catch-up in psychomotor development. 5. After the age of 6 years facial stigmata became more evident with short philtrum of the upper lip and broad and large upper incisors. 6. Tendency to truncular obesity with rest hypotonia and poor muscle development after the ages of 6 to 8 years. The clinical findings and follow-up data in the present four children with Cohen syndrome illustrate that the diagnosis of Cohen syndrome in infancy is very difficult.

Ocular manifestations in Delleman syndrome (Oculocerebrocutaneous syndrome, OCC-syndrome) and encephalocraniocutaneous lipomatosis (ECCL). Report of three cases

The authors present two patients with Delleman syndrome and one in with possible ECCL. Two boys with Delleman syndrome showed characteristic dysmorphic features with cerebral, ocular and skin malformations. The ocular anomalies consisted of eyelid coloboma, microphthalmia, iris coloboma and epibulbar lypodermoids. A third boy with possible ECCL syndrome had limbal lypodermoids, ectopia pupillae and aberrant iris tissue in the right eye. He showed an ipsilateral focal dermal hypoplastic defect within an area of alopecia of the scalp.

Gene conversion between red and defective green opsin gene in blue cone monochromacy

Blue cone monochromacy is an X-linked condition in which the function of both the red pigment gene (RCP) and the green pigment gene (GCP) is impaired. Blue cone monochromacy can be due to a red/green gene array rearrangement existing of a single red/green hybrid gene and an inactivating C203R point mutation in GCP. We describe here a family with blue cone monochromacy due to the presence of the C203R mutation in both RCP and GCP. The flanking sequences of the C203R mutation in exon 4 of RCP were characteristic for GCP, indicating that this mutation was transferred from GCP into RCP by gene conversion.

Unilateral cytomegalovirus retinitis in a patient with immunoglobulin G2 deficiency

A benign course of cytomegalovirus (CMV) retinitis is reported in a young patient with selective immunoglobulin G2 (IgG2) deficiency, after corticosteroid treatment for inflammatory pulmonary disease. IgG2 deficiency is a specific disorder of humoral immunity and has little to do with defense against viruses. This case suggests that CMV retinitis can occur in patients with IgG2 deficiency, who have received steroids in a presumedly nonimmunosuppressive dose for associated respiratory disease.

Features of mtDNA mutation patterns in European pedigrees and sporadic cases with Leber hereditary optic neuropathy

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Chromosome aberrations in fibrous dysplasia

We report the cytogenetic findings of two cases of fibrous dysplasia, one occurring in the tibia, the other in the sphenoid. Both cases exhibited only one chromosome change: a t(6;11)(q15;p15) in the first case, a derivative chromosome 2 in the second. The previous cytogenetic report on fibrous dysplasia revealed only numerical changes. The significance of these inconsistent chromosomal findings in fibrous dysplasia is unclear.

Identification of a key recombinant which assigns the incomplete congenital stationary night blindness gene proximal to MAOB

The gene for complete congenital stationary night blindness (CSNB1) has been assigned to the Xp11.3 region. However, little evidence has been provided for the assignment of the incomplete congenital stationary night blindness gene (CSNB2). Here we present the clinical and molecular data from a CSNB2 family which show a key recombinant assigning the CSNB2 gene proximal to MAOB.

DNA carrier detection in X-linked progressive cone dystrophy

X-linked progressive cone dystrophy (XLPCD) is characterized by progressive macular atrophy, abnormal colour vision, reduced cone responses in ERG, and reduced visual acuity. XLPCD may be genetically heterogeneous. Therefore, carrier detections by DNA analysis may only be carried out in those families in which the position of the gene locus can be clearly established. Here, we describe the first DNA carrier detections in XLPCD.

Heterogeneity versus variability in megalocornea-mental retardation (MMR) syndromes: report of new cases and delineation of 4 probable types

Megalocornea (corneal diameter > or = 13 mm) is associated with mental and neurological impairment, and minor anomalies in Neuhäuser syndrome (megalocornea-mental retardation syndrome). Here we report 4 new cases of megalocornea and mental retardation. Those unrelated patients have a consistent pattern of anomalies with possible recessive inheritance which clearly differs from that of the original patients of Neuhäuser et al. [1975]. We discuss the heterogeneity of the syndromes with megalocornea and mental retardation. Based on these cases and on a review of the literature, we suggest a provisional clinically oriented classification in 5 subtypes: (1) a recessive form type Neuhäuser (with iris hypoplasia and minor anomalies), (2) a recessive form type Frank-Temtamy (with camptodactyly, scoliosis and growth retardation), (3) a recessive type 3, including our 4 personal cases (with normal irides, severe hypotonia, relative or absolute macrocephaly and minor anomalies), (4) a possible Frydman type (with normal irides, megalencephaly and obesity), and (5) provisionally unclassifiable cases.

Congenital ectropion uveae with glaucoma

Congenital ectropion uveae (CEU) is a rare, non progressive anomaly characterised by the presence of iris pigment epithelium on the anterior surface, an anterior iris insertion, dysgenesis of the drainage angle and glaucoma. The condition is characteristically unilateral and rarely hereditary. The current theory of development arrest is discussed. We report three cases with CEU of which two already developed glaucoma. All patients with CEU should be carefully examined periodically to detect glaucoma.

Osteoporosis-pseudoglioma syndrome

Two patients with osteoporosis pseudoglioma syndrome are described. Both are single children, born to nonconsanguineous, healthy parents. The first patient, a 17-year-old girl, had serious visual impairment since birth. She is severely dwarfed and has major skeletal deformities resulting in inability to walk since age 2 years. The second patient is an 18-year-old girl with unilateral neonatal blindness, short stature and deformities, mainly of pelvis and lower limbs. She has been able to walk with support up to now. The clinical and radiological findings in these 2 patients reflect the clinical variability of the condition. Results of collagen studies in both patients are normal and differentiate this condition clearly from severe osteogenesis imperfecta, which it resembles.

Persisting chloroquine-induced myasthenia?

A middle-age woman had intermittently had chloroquine as an antimalarial agent for 21 years. Although she had discontinued the drug for more than 10 years due to occurrence of a retinopathy, mild ocular myasthenic symptoms persisted. Cardiac conduction disturbances were detected as well. A quadriceps muscle biopsy revealed mild neurogenic changes and interstitial lymphorrhages. The decremental response after repetitive stimulation was reversed by edrophonium administration. The history suggests that the persisting myasthenia might have been caused by chloroquine intake.

Functional quantification of diaphany

Intraocular straylight can be measured, in clinical as well as normal cases, by the direct compensation technique. Intraocular straylight is known to originate from the cornea, lens and fundus. We have studied a fourth source: the translucency of the iris and surrounding ocular wall. For lightly-pigmented normal eyes this source proved to be important. In the present paper results are reported from a patient with X-linked megalocornea. He had diaphany of the iris, as is common in these patients, and photophobic complaints. Quantitative measurements showed that the translucency was much increased so that the intraocular straylight was far above the normal level.

The Hermansky-Pudlak syndrome. Variable reaction to 1-desamino-8D-arginine vasopressin for correction of the bleeding time

The effect of the synthetic vasopressin derivative 1-desamino-8D-arginine vasopressin (DDAVP = Minrin) on bleeding time was studied in nine patients with Hermansky-Pudlak syndrome; four of them were Dutch, five were Belgian. Shortening of bleeding time was observed in four of the patients with this type of storage pool disease; in one patient the response was equivocal, in two patients the response was not dramatic and in two there was no response at all. DDAVP may be useful in managing the bleeding disorder in some patients with Hermansky-Pudlak syndrome. Therefore, every patient with this syndrome should be tested with DDAVP as a preventive measure.

Waardenburg syndrome, Hirschsprung megacolon, and Marcus Gunn ptosis

A patient with Waardenburg syndrome type II associated with Hirschsprung megacolon and Marcus Gunn ptosis is presented. It is suggested that these different anomalies are manifestations of the same neurocrestopathy.

Dominant optic nerve atrophy with progressive hearing loss and chronic progressive external ophthalmoplegia (CPEO)

This paper describes a family where chronic progressive external ophthalmoplegia is associated with dominant optic atrophy and progressive sensorineural deafness. This may be a possible association in the same family of two diseases: progressive external ophthalmoplegia and dominant optic atrophy with progressive hearing loss. However, we believe that this family represents an unusual manifestation of ophthalmoplegia plus.