Severe Thrombocytopenia Due to Bone Marrow Failure in Children With Dyskeratosis Congenita Does Not Respond to Eltrombopag Treatment: Case Series

Dyskeratosis congenita is a rare inherited disease with classic cutaneous symptoms, sometimes accompanied with more severe extracutaneous manifestations such as bone marrow failure, which can be lethal. Eltrombopag is an orally available thrombopoietin receptor agonist in clinical use for increasing platelet levels in patients with immune thrombocytopenia and aplastic anemia. Here, 3 pediatric patients with dyskeratosis congenita are presented with varying disease severity, in which off-label eltrombopag treatment had no clinical effect on bone marrow failure. This, in addition to the negative results in a previous case report, supports the preclusion of eltrombopag use in dyskeratosis congenita.

Progression of liver disease and portal hypertension in dyskeratosis congenita and related telomere biology disorders

BACKGROUND AND AIMS

Dyskeratosis congenita (DC) and related telomere biology disorders (TBD) are characterized by very short telomeres and multisystem organ involvement including liver disease. Our study aimed to characterize baseline hepatic abnormalities in patients with DC/TBD and determine risk factors associated with liver disease progression.

APPROACH AND RESULTS

A retrospective review was performed on a cohort of 58 patients (39 males) with DC/TBD who were prospectively evaluated at a single institute from 2002 to 2019. The median age at initial assessment was 18 (1.4-67.6) years, and median follow-up duration was 6 (1.4-8.2) years. Patients with autosomal or X-linked recessive inheritance and those with heterozygous TINF2 DC were significantly younger, predominantly male, and more likely to have DC-associated mucocutaneous triad features and severe bone marrow failure compared with autosomal dominant-non- TINF2 DC/TBD patients. Liver abnormality (defined at baseline assessment by laboratory and/or radiological findings) was present in 72.4% of patients with predominantly cholestatic pattern of liver enzyme elevation. Clinically significant liver disease and portal hypertension developed in 17.2% of patients during the 6-year follow-up; this progression was mainly seen in patients with recessive or TINF2 -associated DC. Significant risk factors associated with progression included the presence of pulmonary or vascular disease.

CONCLUSIONS

Our experience shows a high prevalence of cholestatic pattern of liver abnormality with progression to portal hypertension in patients with DC/TBD. Presence of pulmonary and/or vascular disease in patients with recessive or TINF2 DC was an important predictor of liver disease progression, suggesting the need for increased vigilance and monitoring for complications in these patients.

Spectrum of Liver Pathology in Dyskeratosis Congenita

Dyskeratosis congenita (DC) is a rare multisystemic disorder associated with defective telomere maintenance. Frequent clinical manifestations of DC include reticular skin pigmentation, dystrophic nails, oral leukoplakia, and bone marrow failure. Hepatic disturbances are reported to occur in 7% of DC patients. This study aimed to evaluate the histopathologic spectrum of hepatic involvement in this disorder. DC patients with liver tissue in the pathology database at Boston Children's Hospital from 1995 to 2022 were identified. Clinical and pathologic information was documented. Thirteen specimens from 11 DC patients were included (M:F = 7:4; median age at the time of liver tissue evaluation: 18 y). DC-associated gene mutations were identified in 9 patients; TERF1-interacting nuclear factor 2 ( TINF2) was the most frequently represented gene mutation, seen in 4 patients. All patients had bone marrow failure, whereas dystrophic nails, cutaneous abnormal pigmentation, and oral leukoplakia were noted in 73%, 64%, and 55% of patients, respectively. Seven patients underwent bone marrow transplants before biopsy/autopsy (median interval of 45 mo). Histologically, 3 of 4 patients who presented with portal hypertension showed noncirrhotic changes (nodular regenerative hyperplasia and/or obliterative portal venopathy), whereas prominent central and sinusoidal fibrosis was noted in patients with intrahepatic shunting and those showing features of chronic passive congestion. All cases showed hepatocyte anisonucleosis. One patient developed hepatic angiosarcoma, and another 1 had colorectal adenocarcinoma metastatic to the liver. DC patients show heterogeneous histologic findings in their liver. The findings of noncirrhotic portal hypertension, intrahepatic shunting, and angiosarcoma suggest vascular functional/structural pathology as a possible unifying etiology of hepatic manifestations of DC.

Multiple bilateral hip fractures in a patient with dyskeratosis congenita caused by a novel mutation in the PARN gene

We report a case of a young male patient with clinical signs of dyskeratosis congenita who presented with multiple bilateral low-traumatic hip fractures. Whole exome sequencing (WES) showed a previously unreported mutation in the poly(A)-specific ribonuclease (PARN) gene. Zoledronic acid 5 mg over 3 years was effective at preventing further fractures. A male patient was referred to our clinic at age 24 due to multiple bilateral hip fractures. At the time of admission, the patient's height was 160 cm and weight 40 kg; bone mineral density (BMD) at the lumbar spine was normal (L1-L4 0.0 Z-score). The patient was found to have abnormal skin pigmentation, hyperkeratosis of palms and soles, nail dystrophy, and signs of bone marrow failure (BMF). Bone fragility first presented at 5 years old with a wrist fracture, followed by multiple bilateral low-traumatic hip fractures without falls from 14 to 24 years. WES showed a previously unreported mutation (NM_002582.3: c.1652delA; p.His551fs) in the poly(A)-specific ribonuclease (PARN) gene. Flow fish telomere measurement result was 5.9 (reference range 8.0-12.6), which is consistent with the DC diagnosis. Permanent fixation with internal metal rods and zoledronic acid 5 mg over 3 years was effective at preventing further fractures over 4 years of follow-up. Additionally, BMF did not progress over 4 years of observation. DC associated with PARN gene mutations might predispose to low-traumatic multiple hip fractures in adolescents and young adults. Treatment with zoledronic acid in this case was effective and safe at preventing further fractures.

Diverse Pathological Findings of Interstitial Lung Disease in a Patient with Dyskeratosis Congenita

A 42-year-old man with a history of surgery for tongue cancer was referred to our hospital due to an abnormal chest shadow. High-resolution computed tomography showed lower lobe reticulation. A physical examination revealed nail dystrophy, oral leukoplakia, and reticulated hypopigmentation. Lung biopsy revealed subpleural and perilobular fibrosis, suggestive of usual interstitial pneumonia. However, multiple pathological findings, including homogenous fibrosis and cell infiltration in the centrilobular region, which were compatible with nonspecific interstitial pneumonia, and bronchiolitis were also seen. Genetic testing showed a hemizygous missense mutation in the DKC1 gene, and the patient was diagnosed with dyskeratosis congenita. Although anti-fibrotic therapy was initiated, the patient's respiratory function has continued to decrease.

Dyskeratosis congenita and a rare brain abscess

Dyskeratosis congenita is a rare inheritable disease which causes peculiar dermatological features and bone marrow failure with an increased risk of severe infections and neoplasia. Actinomyces spp. is part of the oral cavity flora. Invasive infections are mostly seen in immunocompromised hosts. We report a case of a rare central nervous infection and an underling inheritable disease.

Chronic sole ulcer in a child with dyskeratosis congenita: An atypical wound successfully treated with punch grafting

Dyskeratosis congenita (DC) is an unusual inherited disease characterized by the triad of mucosal leukoplakia, nail dystrophy, and skin pigmentation. Hyperkeratosis of the palms and soles is another reported skin finding. This hyperkeratosis can lead to fissures, chronic erosion, and deep ulcerations. These atypical wounds are not only a diagnostic but a therapeutic challenge for clinicians, and there are no standardized treatments for these types of chronic wounds. Punch grafting is a traditional and minimally invasive technique to enhance wound healing, and it has been associated with significant and quick pain reduction in ulcers with various underlying causes. Herein, we describe a patient with DC with a chronic and refractory plantar ulcer successfully treated with punch grafting.

Fatal Acute Exacerbation of Familial Interstitial Pneumonia Complicated with Dyskeratosis Congenita after Influenza Virus B Infection

Dyskeratosis congenita (DC) is occasionally complicated in patients with familial interstitial pneumonia (FIP). However, there have been no reports of FIP patients with DC that develop acute exacerbation (AE). We herein report a FIP patient with DC that showed AE of FIP after influenza virus B infection. Although DC is a rare disease in clinical practice, physicians should keep in mind that FIP combined with DC has the potential to cause AE.

Paracrine Interaction of Cancer Stem Cell Populations Is Regulated by the Senescence-Associated Secretory Phenotype (SASP)

Dyskeratosis congenita is a telomere DNA damage syndrome characterized by defective telomere maintenance, bone marrow failure, and increased head and neck cancer risk. The Pot1b^-/-;Terc^+/- mouse exhibits some features of dyskeratosis congenita, but head and neck cancer was not reported in this model. To model the head and neck cancer phenotype, we created unique Pot1b- and p53-null-mutant models which allow genetic lineage tracing of two distinct stem cell populations. Loss of Pot1b expression depleted stem cells via ATR/Chk1/p53 signaling. Tumorigenesis was inhibited in Pot1b^-/-;p53^+/+ mice due to cellular senescence. Pot1b^-/-;p53^-/- tumors also exhibited senescence, but proliferated and metastasized with expansion of Lgr6⁺ stem cells indicative of senescence-associated secretory phenotype. Selective depletion of the small K15⁺ stem cell fraction resulted in reduction of Lgr6⁺ cells and inhibition of tumorigenesis via senescence. Gene expression studies revealed that K15⁺ cancer stem cells regulate Lgr6⁺ cancer stem cell expansion via chemokine signaling. Genetic ablation of the chemokine receptor Cxcr2 inhibited cancer stem cell expansion and tumorigenesis via senescence. The effects of chemokines were primarily mediated by PI3K signaling, which is a therapeutic target in head and neck cancer. IMPLICATIONS: Paracrine interactions of cancer stem cell populations impact therapeutic options and patient outcomes.

[A Case of Stage ⅣRectal Cancer with Dyskeratosis Congenita]

A 27-year-old man was diagnosed with dyskeratosis congenita from DKC1 gene mutation at 9 years of age and had been followed-up regularly.An upper gastrointestinal endoscopy performed for vomiting revealed gastric varices.Further examination resulted in a diagnosis of Stage Ⅳrectal cancer with portal hypertension, splenomegaly, liver, and lung metastasis and he was referred to our department.A laparoscopic splenectomy was performed, followed by a laparoscopic low anterior resection for rectal cancer.Subsequently, resection of the pulmonary and liver metastasis was performed, resulting in macroscopic radical resection.However, 3 months after the hepatectomy, unresectable multiple lung metastasis was detected and he received 5 courses of chemotherapy with cetuximab.A grade 3 skin rash was observed and chemotherapy was discontinued. After 5 courses, he had pneumothorax and received drainage.He had sudden respiratory failure 2 days after pleural adhesion therapy of OK-432 was performed.He was diagnosed with interstitial pneumonia induced by OK-432 and steroid pulse therapy, which resulted in his death without improvement 21 days after admission.

A case report of heterozygous TINF2 gene mutation associated with pulmonary fibrosis in a patient with dyskeratosis congenita

RATIONALE

Dyskeratosis congenita (DC) is a rare inherited disease characterized by the classical mucocutaneous triad. Pulmonary fibrosis, bone marrow failure, and solid tumors are the main causes of mortality in DC. Pathogenic variants in TERT, TERC, and DKC1 have been identified in individuals with familial pulmonary fibrosis. Mutations in TINF2 gene have been reported to be associated with bone marrow failure in most cases. However, the relationship between TINF2 mutation and pulmonary fibrosis is not yet clear.

PATIENT CONCERNS

Here, we report the case of a 32-year-old woman presented with irritating cough for 2 years and progressive breathlessness for 6 months.

DIAGNOSES

The patient was diagnosed with DC based on the following clinical evidences. Along with some family members, she had the typical mucocutaneous triad and pulmonary fibrosis. A heterozygous mutation (c.844C>T), located in exon 6 of TINF2 gene, that changed arginine to cysteine (Arg282Cys) was identified in this proband by whole exome sequencing.

INTERVENTIONS

The patient received corticosteroid therapy but refused to receive lung transplantation.

OUTCOMES

The proband died of respiratory failure 4 months after the diagnosis. The missense mutation was located in the conserved region of TINF2 gene and predicted to be deleterious by altering the protein structure.

LESSONS

Lung transplantation should be considered for improved survival of patients with DC, and pulmonary fibrosis. Whole exome and whole genome sequencing should be widely used in the identification of such rare genetic variants for clinical diagnosis. The study of DC with pulmonary fibrosis can provide a more appropriate means of clinical research and therapy to the unfortunate patients who suffer from this rare disorder.

Progressive reticulate skin pigmentation and anonychia in a patient with bone marrow failure

KEY TEACHING POINTS.

RETINAL VASCULAR TORTUOSITY AND EXUDATIVE RETINOPATHY IN A FAMILY WITH DYSKERATOSIS CONGENITA MASQUERADING AS FAMILIAL EXUDATIVE VITREORETINOPATHY

PURPOSE

To report a novel presentation of dyskeratosis congenita masquerading as familial exudative vitreoretinopathy.

METHODS

Observational case series involving single family and literature review.

RESULTS

A brother and sister were diagnosed with familial exudative vitreoretinopathy at ages 4 and 2, respectively. Both patients were managed with laser photocoagulation. Eight years after the initial presentation, both siblings developed pancytopenia secondary to bone marrow failure. Laboratory work-up revealed severely shortened telomere length in both patients, and genetic testing revealed a missense mutation in the gene that encodes the reverse transcriptase component of telomerase, confirming the diagnosis of dyskeratosis congenita. The father of both children was a carrier of the same mutation, who exhibited marked retinal vascular tortuosity of the second-order vessels.

CONCLUSION

Dyskeratosis congenita is a severe multisystem disorder, which should be considered in cases of pediatric exudative retinopathies with concurrent signs and/or symptoms of bone marrow failure.

[Recurrent pulmonary infection and oral mucosal ulcer]

An 8-year-old girl who had experienced intermittent cough and fever over a 3 year period, was admitted after experiencing a recurrence for one month. One year ago the patient experienced a recurrent oral mucosal ulcer. Physical examination showed vitiligo in the skin of the upper right back. Routine blood tests and immune function tests performed in other hospitals had shown normal results. Multiple lung CT scans showed pulmonary infection. The patient had recurrent fever and cough and persistent presence of some lesions after anti-infective therapy. The antitubercular therapy was ineffective. Routine blood tests after admission showed agranulocytosis. Gene detection was performed and she was diagnosed with dyskeratosis congenita caused by homozygous mutation in RTEL1. Patients with dyskeratosis congenita with RTEL1 gene mutation tend to develop pulmonary complications. Since RTEL1 gene sequence is highly variable with many mutation sites and patterns and can be inherited via autosomal dominant or recessive inheritance, this disease often has various clinical manifestations, which may lead to missed diagnosis or misdiagnosis. For children with unexplained recurrent pulmonary infection, examinations of the oral cavity, skin, and nails and toes should be taken and routine blood tests should be performed to exclude dyskeratosis congenita. There are no specific therapies for dyskeratosis congenita at present, and when bone marrow failure and pulmonary failure occur, hematopoietic stem cell transplantation and lung transplantation are the only therapies. Androgen and its derivatives are effective in some patients. Drugs targeting the telomere may be promising for patients with dyskeratosis congenita.

Diffuse Mesangial Sclerosis in a Child With Dyskeratosis Congenita Leading to End-stage Renal Disease

Dyskeratosis congenita (DC) is a very rare inherited disorder. It is caused by dysfunction of telomere maintenance. It involves RNA telomerase components relevant to various mutations leading to a classic triad of physical findings consisting of nail dystrophy of the hands and feet, mucosal leukoplakia, and reticular pigmentation of the skin, most commonly on the head, neck, and trunk. Bone marrow failure along with pulmonary complications and malignancies are all common causes of premature death in patients with DC as well as other abnormalities. We report a new case of DC with impure nephrotic syndrome relevant to histopathologic signs of a diffuse mesangial sclerosis, leading to an early end-stage renal disease. Challenges remain to understand the diverse spectrum of DC especially in children. To the best of our knowledge this is the first case of DC associated to diffuse mesangial sclerosis.

Bilateral Proliferative Retinopathy Associated With Hoyeraal-Hreidarsson Syndrome, a Severe Form of Dyskeratosis Congenita

Dyskeratosis congenita (DC) is the prototypical member of a family of diseases caused by defective telomere maintenance. These "telomeropathies" also include Hoyeraal-Hreidarsson syndrome (HH) and Revesz syndrome, which are severe forms of dyskeratosis congenita, as well as a subset of idiopathic pulmonary fibrosis, aplastic anemia, and Coats' plus syndrome. Retinopathy has only rarely been reported in DC and HH, but is universally present in Coats' plus and Revesz syndromes. The care of these patients is typically a multidisciplinary effort, and this should include monitoring by an ophthalmologist.

Fatal Hemorrhagic Gastrointestinal Angioectasia after Bone Marrow Transplantation for Dyskeratosis Congenita

Dyskeratosis congenita (DC) is a rare inherited disease in which the telomere complex cannot be maintained. Shortened telomeres can cause a number of clinical conditions. We herein report a case of unrelated bone marrow transplantation due to aplastic anemia associated with DC. The patient died of uncontrollable refractory intestinal bleeding. Three cases of DC with life-threatening hemorrhaging after transplantation have been reported; however, the bleeding origin could not be determined. Our case is the only patient in which a gastrointestinal bleeding point, jejunal multiple angioectasia, was determined.

Hepatic Angiosarcoma with Dyskeratosis Congenita

Nail dystrophy, oral leukoplakia and abnormal skin pigmentation are the defining features of dyskeratosis congenita. Dyskeratosis congenita is a disorder of poor telomere maintenance and is known to increase the risk of developing multiple types of malignancy. However, there are few reports of liver tumors arising in dyskeratosis congenita patients. We herein report the second case of hepatic angiosarcoma arising from dyskeratosis congenita: a 23-year-old man was introduced to our hospital due to the detection of multiple tumors in the liver. A histological analysis showed angiosarcoma that stained positive for antibodies to both CD31 and blood coagulation factor VIII.

Aplastic anemia and Hoyeraal-Hreidarsson syndrome

A 2-year-old girl patient was admitted with intractable diarrhea, respiratory infections, and seizures. She was the first child of the first-degree parents. She was born at term with a birth weight of 2300 g. Physical examination revealed weight 6800 g, height 76 cm, and head circumference 41 cm, below the third percentile. Findings included sparse and dull hair, nail dystrophy, and proximally located thumbs (Figure). Aphthous lesions were observed on the oral mucosa. Neurologic examination disclosed poor head control. She could not sit without support and had hyper-reactive deep tendon reflexes.

Zebrafish models for dyskeratosis congenita reveal critical roles of p53 activation contributing to hematopoietic defects through RNA processing

Dyskeratosis congenita (DC) is a rare bone marrow failure syndrome in which hematopoietic defects are the main cause of mortality. The most studied gene responsible for DC pathogenesis is DKC1 while mutations in several other genes encoding components of the H/ACA RNP telomerase complex, which is involved in ribosomal RNA(rRNA) processing and telomere maintenance, have also been implicated. GAR1/nola1 is one of the four core proteins of the H/ACA RNP complex. Through comparative analysis of morpholino oligonucleotide induced knockdown of dkc1 and a retrovirus insertion induced mutation of GAR1/nola1 in zebrafish, we demonstrate that hematopoietic defects are specifically recapitulated in these models and that these defects are significantly reduced in a p53 null mutant background. We further show that changes in telomerase activity are undetectable at the early stages of DC pathogenesis but rRNA processing is clearly defective. Our data therefore support a model that deficiency in dkc1 and nola1 in the H/ACA RNP complex likely contributes to the hematopoietic phenotype through p53 activation associated with rRNA processing defects rather than telomerase deficiency during the initial stage of DC pathogenesis.

The genetics of dyskeratosis congenita

Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome associated with characteristic mucocutaneous features and a variable series of other somatic abnormalities. The disease is heterogeneous at the genetic and clinical levels. Determination of the genetic basis of DC has established that the disease is caused by a number of genes, all of which encode products involved in telomere maintenance, either as part of telomerase or as part of the shelterin complex that caps and protects telomeres. There is overlap at the genetic and clinical levels with other, more common conditions, including aplastic anemia (AA), pulmonary fibrosis (PF), and liver cirrhosis. Although part of the spectrum of disorders known to be associated with DC, it has emerged that mutations in telomere maintenance genes can lead to the development of AA and PF in the absence of other DC features. Here we discuss the genetics of DC and its relationship to disease presentation.

Dyskeratosis congenita with portal hypertension of unknown etiology

Dyskeratosis Congenita (DKC) is a rare progressive bone marrow disorder associated with multi-systemic involvement. It is also characterized by triad of abnormal skin pigmentation, nail dystrophy and mucosal leukoplakia. Liver cirrhosis and portal hypertension are said to be uncommon among these patients. We hereby report a case of an adult male who presented with pancytopenia, abnormal skin pigmentation, nail dystrophy and mucosal leukoplakia. Skin biopsies along with clinical features confirmed the case. Imaging studies were reported as suggestive of and portal hypertension. Liver biopsy done but non-conclusive. Patient's one son and one daughter also had similar skin pigmentation.

Short telomeres compromise β-cell signaling and survival

The genetic factors that underlie the increasing incidence of diabetes with age are poorly understood. We examined whether telomere length, which is inherited and known to shorten with age, plays a role in the age-dependent increased incidence of diabetes. We show that in mice with short telomeres, insulin secretion is impaired and leads to glucose intolerance despite the presence of an intact β-cell mass. In ex vivo studies, short telomeres induced cell-autonomous defects in β-cells including reduced mitochondrial membrane hyperpolarization and Ca²⁺ influx which limited insulin release. To examine the mechanism, we looked for evidence of apoptosis but found no baseline increase in β-cells with short telomeres. However, there was evidence of all the hallmarks of senescence including slower proliferation of β-cells and accumulation of p16^INK4a. Specifically, we identified gene expression changes in pathways which are essential for Ca²⁺-mediated exocytosis. We also show that telomere length is additive to the damaging effect of endoplasmic reticulum stress which occurs in the late stages of type 2 diabetes. This additive effect manifests as more severe hyperglycemia in Akita mice with short telomeres which had a profound loss of β-cell mass and increased β-cell apoptosis. Our data indicate that short telomeres can affect β-cell metabolism even in the presence of intact β-cell number, thus identifying a novel mechanism of telomere-mediated disease. They implicate telomere length as a determinant of β-cell function and diabetes pathogenesis.

Dyskeratosis congenita

Dyskeratosis congenita (DC) is a multisystem inherited syndrome exhibiting marked clinical and genetic heterogeneity. In its classic form, it is characterized by mucocutaneous abnormalities, BM failure, and a predisposition to cancer. BM failure is the principal cause of premature mortality. Studies over the last 15 years have led to significant advances, with 8 DC genes (DKC1, TERC, TERT, NOP10, NHP2, TIN2, C16orf57, and TCAB1) having been characterized. Seven of these are important in telomere maintenance either because they encode components of the telomerase enzyme complex (DKC1, TERC, TERT, NOP10, NHP2, and TCAB1) or the shelterin complex (TINF2). DC is therefore principally a disease of defective telomere maintenance and patients usually have very short telomeres. The genetic advances have led to the unification of DC with several other disorders, including the severe multisystem disorders Hoyeraal-Hreidarsson and Revesz syndromes, as well as a subset of patients with aplastic anemia, myelodysplasia, leukemia, and idiopathic pulmonary fibrosis. This wide spectrum of diseases ranging from classic DC to aplastic anemia can be regarded as disorders of defective telomere maintenance-"the telomereopathies." These advances have increased our understanding of normal hematopoiesis and highlighted the important role of telomerase and telomeres in human biology. They are also facilitating the diagnosis (especially when presentation is atypical) and management of DC.

Ocular and orbital manifestations of the inherited bone marrow failure syndromes: Fanconi anemia and dyskeratosis congenita

PURPOSE

The inherited bone marrow failure syndromes (IBMFS) are a heterogeneous group of genetic disorders that share the inability of the bone marrow to produce an adequate number of blood cells. The 4 most frequent syndromes are Fanconi anemia (FA), dyskeratosis congenita (DC), Diamond-Blackfan anemia (DBA), and Shwachman-Diamond syndrome (SDS). All 4 syndromes have been associated with various physical abnormalities. As part of a genotype/phenotype/cancer susceptibility study, we determined the prevalence of ophthalmic manifestations in these 4 syndromes.

DESIGN

Cross-sectional study of a patient cohort.

PARTICIPANTS

Seventy-five patients with an IBMFS and 121 of their first-degree relatives were seen in the National Eye Institute, National Institutes of Health, from 2001 to 2007. The patient group included 22 with FA, 28 with DC, 19 with DBA, and 6 with SDS.

METHODS

Every participant underwent a complete ophthalmic evaluation and digital facial photography with an adhesive paper ruler on the patient's forehead for an internal measure of scale. Interpupillary distance (IPD), inner canthal distance (ICD), outer canthal distance (OCD), palpebral fissure length (PFL), and corneal diameter (CD) were measured. Thirteen of the 22 patients with FA underwent axial length (AL) measurements by A-scan ultrasonography.

MAIN OUTCOME MEASURES

Type and prevalence of ophthalmic manifestations.

RESULTS

Ninety-five percent of patients with FA had at least 1 abnormal parameter, and 25% of patients had at least 4 abnormal parameters. Eighty-two percent of patients had small palpebral fissures, 69% of patients had simple microphthalmia, 64% of patients had small OCD, 55% of patients had microcornea, 28% of patients had ptosis, and 6% of patients had epicanthal folds. In patients with DC, abnormalities of the lacrimal drainage system (29%) were the most prevalent findings, followed by retinal abnormalities (pigmentary changes, retinal neovascularization, retinal detachment, exudative retinopathy) in 21%, cicatricial entropion with trichiasis and blepharitis in 7% each, and sparse eyelashes and congenital cataract in 3.5% each. No significant ophthalmic abnormalities were seen in patients with DBA or SDS.

CONCLUSIONS

Syndrome-specific ocular findings are associated with FA and DC and may antedate diagnosis of the specific syndrome. Early recognition of these abnormalities is important for optimal management.

Dyskeratosis congenita and limbal stem cell deficiency

In light of the latest developments in the field of molecular hematology, we herein discuss the reported cases that have presented dyskeratosis congenita as one of the inherited stem cell diseases causing limbal stem cell deficiency.

Dyskeratosis congenita

Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome characterized clinically by the triad of abnormal nails, reticular skin pigmentation, and oral leukoplakia, and is associated with high risk of developing aplastic anemia, myelodysplastic syndrome, leukemia, and solid tumors. Patients have very short germline telomeres, and approximately half have mutations in one of six genes encoding proteins that maintain telomere function. Accurate diagnosis of DC is critical to ensure proper clinical management, because patients who have DC and bone marrow failure do not respond to immunosuppressive therapy and may have increased morbidity and mortality associated with hematopoietic stem cell transplantation.

All in the family: disclosure of "unwanted" information to an adolescent to benefit a relative

Ethical assessments of clinical decisions are typically based on the preferences and interests of the individual patient. However, some clinical interventions, such as genetic testing or organ donation, may involve multiple family members. In these cases, one family member may have the potential to benefit, while another family member is exposed to potential physical or psychological risk. In the research setting, the balancing of benefits and risks between family members may be further complicated by uncertainty about their magnitude and likelihood. In addition, when the individual facing these apparently uncompensated risks is a child, the situation becomes particularly ethically complicated, as we appreciated in a recent case. Investigators at the National Cancer Institute were faced with a decision about whether it would be appropriate to disclose apparently "unwanted" research test results (length of telomeres in leukocyte subsets) to an adolescent about risk of future disease (dyskeratosis congenita), possibly causing psychological harm and an ethical wrong. These issues were not expected at the outset of the family's study participation but rather emerged with new data about the research tests. Disclosure of the research finding was an important consideration in order to avoid using the adolescent as a stem-cell donor for his sister. Disclosure to the adolescent could not be justified by merely considering the immediate interests and preferences of the adolescent. However, an expanded ethical analysis that considers the adolescent's familial context offers a more complete picture of the adolescent's interests and preferences which provides justification for disclosure.

Oral and dental phenotype of dyskeratosis congenita

Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome that is characterized by lacey reticular hyperpigmentation of the skin, dystrophic nails, mucous membrane leukoplakia and pancytopenia. Diagnosis may be delayed until clinical signs are apparent. Severe pancytopenia frequently causes early mortality of DC patients, who have an increased risk of developing oropharyngeal squamous cell carcinoma. Several case reports have described oral changes in DC, which include oral leukoplakia, increased dental caries, hypodontia, thin enamel structure, aggressive periodontitis, intraoral brown pigmentation, tooth loss, taurodontism and blunted roots. We determined the prevalence of these previously reported findings in a cohort of 17 patients with DC and 23 family members. The most common oral changes in DC patients were oral leukoplakia (65% of the entire DC population), decreased root/crown ratio (75% with sufficient tooth development) and mild taurodontism (57% with sufficient tooth development). From the clinical perspective, a diagnosis of DC or other inherited bone marrow failure syndrome should be considered in young persons with oral leukoplakia, particularly those with no history of smoking. Multiple permanent teeth with decreased root/crown ratios further suggest DC.

Dyskeratosis congenita associated with hypocellular myelodysplastic syndrome: a case report

A 16-year-old female patient presented with complaints of malaise, dizziness, syncope, and nausea of 1-week duration. On dermatologic examination there were telangiectasias, atrophic areas, and poikiloderma with both hypopigmentation and hyperpigmentation on the neck and the proximal parts of the thighs. The bone marrow biopsy specimen showed hypocellularity and dysplastic megakaryocytic and erythroid elements, findings consistent with hypocellular myelodysplastic syndrome, which was further confirmed by cytogenetic studies. Thereafter, she was referred for allogeneic bone marrow transplantation.

Adenocarcinoma gástrico en el síndrome de Zinsser-Cole-Engman

Zinsser-Cole-Engman syndrome is a congenital dyskeratosis that produces cutaneus and hematologic alterations and, in 5% of patients, gastrointestinal neoplasms. We report the case of a 37-year-old man with this syndrome who was diagnosed with gastric adenocarcinoma. This case provides an example of the management that should be followed with these patients in order to identify neoplasms at stages in which treatment is curative.

[Nosologic discussion between Fanconi disease and congenital dyskeratosis: 1 case of congenital bone marrow aplasia]

Based on a case report of aplastic anemia associated with malformation, we discuss the diagnostic criteria and the nosologic problem between the 2 principal aplastic anemia accompanied with malformation: Fanconi disease and dyskeratosis congenita.

CASE REPORT

A 19-year-old girl, issued from a third degree consanguineous marriage, was admitted because of anemic and hemorrhagic syndrome. Physical examination showed several malformations: microphtalmia, brownish spots, generalized hyperpigmentation and ungueal dystrophy without mucosal leucoplasia. Statural and ponderal retardation were noted. On the hemogram there was a pancytopenia and on biopsy, the bone marrow was desertic. The caryotype performed on peripheral blood lymphocytes after sensibilisation with mitomycin C revealed chromosomal instability aspects. Based on these clinical and biological features, the diagnosis of hereditary aplastic anaemia was retained. The patient was given norethandrolone. She died 3 months later by septic shock.

DISCUSSION

Coexistence of aplastic anemia with a malformative syndrome suggests most probably an hereditary form of aplastic anemia. Fanconi anemia is the most frequent. It associates characteristic anomalies of the face, with microphtalmia, brownish spots, statural and ponderal retardation, and thumb anomalies. Ungueal dystrophy, mucosal leucoplasia are almost pathognomonic of congenital dyskeratosis. When the malformative syndrome is not characteristic, the cytogenetic study may also fail to make the differential diagnosis, as was the situation in our case.

Multiple constitutional aetiological factors in bone marrow failure syndrome (BMFS) patients from north India

BACKGROUND AND OBJECTIVES

A large number of patients diagnosed with bone marrow failure syndromes (BMFS), comprising aplastic anaemia (AA) and myelodysplastic syndromes (MDS), remain aetiologically uncharacterized worldover, especially in resource constrained set up. We carried out this study to identify a few constitutional causes in BMFS patients attending a tertiary care hospital in north India.

METHODS

Peripheral blood lymphocyte cultures were performed (with and without clastogens) in a cohort of 135 consecutive BMFS patients, in order to detect Fanconi anaemia (FA), Down's syndrome (+21), trisomy 8 (+8) and monosomy 7 (-7).

RESULTS

Constitutional factors were detected in 17 (12.6%) patients. FA defect was observed in 24.07 percent (13/54), 16.66 percent (1/6) and 2.85 percent (1/35) paediatric aplastic anaemia, paediatric MDS and adult MDS patients respectively. Down's syndrome was detected in 5.00 percent (2/40) adult aplastic anaemia patients. None of the patients revealed trisomy 8 or monosomy 7.

INTERPRETATION AND CONCLUSION

Presence of an underlying factor determines appropriate management, prognostication, family screening and genetic counselling of BMFS patients. Special tests required to confirm or exclude constitutional aetiological factors are not available to majority of the patients in our country. Diepoxybutane (DEB) test yielded better results than mitomycin C (MMC) test in our experience.

A case of dyskeratosis congenita with portal hypertension associated with jugular venous anomaly

Dyskeratosis congenita is an unusual inherited disease characterized by the triad of abnormal skin pigmentation, nail dystrophy and mucosal leukoplakia. Bone marrow failure and various abnormalities including genitourinary, pulmonary, skeletal, neurological, ophthalmic, dental and gastrointestinal have been reported. Portal hypertension is an extremely rare manifestation. Although arterio-venous fistulas in the lungs have been reported, gross peripheral vascular abnormality associated with the disease has not been published until now. We describe a case of dyskeratosis congenita with portal hypertension and associated coagulopathy in whom transjugular liver biopsy could not be performed because of a vascular anomaly at the bifurcation of the internal jugular and subclavian veins.

Interdisciplinary approach to treat dyskeratosis congenita associated with severe aplastic anemia: A case report

This paper reports on a 4-year-old male who had dyskeratosis congenita and who acquired severe aplastic anemia. The patient developed hyperpigmentation of the face, neck and chest region, arms, shoulders and legs. In addition, he had dry skin, deformed fingernails and toenails, sparse hair and eyebrows and hyperkeratosis of the dorsum of the hands and feet. Laboratory and histological analysis revealed severe pancytopenia and dyserythropoiesis of red blood cells, hypocellularity of white blood cells and decreased megakaryocytes with dysplasia. The intraoral examination identified bleeding gums; petechiae of the palate, tongue and cheek mucosa; and an atrophic, smooth and shining dorsal surface of the tongue. There were deep carious lesions in the deciduous mandibular molars and maxillary anterior teeth; as well as mobility of mandibular left canine, which had bone loss. The treatment for oral lesions included diet changes, improved oral hygiene, and extraction of the deciduous teeth destroyed by caries.

Intensive immunosuppression therapy for aplastic anemia associated with dyskeratosis congenita: report of a case

Dyskeratosis congenita (DC) is a very rare inherited disorder characterized by skin pigmentation, nail dystrophy, and mucosal leukoplakia. It is also associated with a variety of noncutaneous abnormalities, such as fatal pulmonary complications, malignancy, and bone marrow failure. We report the case of a 32-year-old man with DC associated with severe aplastic anemia (SAA). The traditional treatment of DC-associated SAA is allogeneic hematopoietic stem cell transplantation (HSCT). However, in this case, an HLA-matched donor was not available. Therefore our patient was given intensive immunosuppressive therapy with antilymphocyte globulin (ALG) and cyclosporine A (CsA). The hemogram findings improved after the treatment, but the patient died of pulmonary complications after being in stable condition for 6 months. The results support the possible use of intensive immunosuppression with ALG and CsA for DC-associated SAA as an alternative treatment for patients who are not eligible for HSCT.

Dyskeratosis congenita: its connections with oral and maxillofacial surgery

Dyskeratosis congenita is characterised by abnormal pigmentation of skin, dystrophy of nails, and mucosal leukoplakia mainly on the tongue. Bone marrow failure, pulmonary complication, and premalignant leukoplakia of the tongue are serious complications of the disease.

Usual interstitial pneumonia complicating dyskeratosis congenita

Dyskeratosis congenita (DC) is a rare disorder characterized by skin hyperpigmentation, nail dystrophy, and leukoplakia of mucous membranes. Pulmonary complications occur in approximately 20% of patients, although the specific histopathologic features, the temporal relationship between the diagnosis of DC and the development of pulmonary fibrosis, and the response to specific treatment are largely undefined. We describe 2 patients with DC who developed usual interstitial pneumonia. Pulmonary fibrosis developed 18 and 38 years after the original manifestations of DC. Both patients died of respiratory failure, 4 and 6 months after lung biopsy. Pulmonary fibrosis in patients with DC may be linked to underlying abnormalities of fibroblast function.