Genetic Spectrum and Clinical Characteristics of Patients with Primary Ciliary Dyskinesia: a Belgian Single Center Study.

PURPOSE: We aimed to examine the correlation between clinical characteristics and the pathogenic gene variants in patients with Primary Ciliary Dyskinesia (PCD). METHODS: We conducted a retrospective single-center study in patients with PCD followed at the University Hospitals Leuven. We included patients with genetically confirmed PCD and described their genotype, data from ultrastructural ciliary evaluation and clinical characteristics. Genotype/phenotype correlations were studied in patients with the most frequently involved genes. RESULTS: We enrolled 74 patients with a median age of 25.58 years. The most frequently involved genes were DNAH11 (n = 23) and DNAH5 (n = 19). The most frequent types of pathogenic variants were missense (n = 42) and frameshift variants (n = 36) and most patients had compound heterozygous variants (n = 44). Ciliary ultrastructure (p < 0.001), situs (p = 0.015) and age at diagnosis (median 9.50 vs 4.71 years, p = 0.037) differed between DNAH11 and DNAH5. When correcting for situs this difference in age at diagnosis was no longer significant (p = 0.973). Patients with situs inversus were diagnosed earlier (p = 0.031). Respiratory tract microbiology (p = 0.161), lung function (cross-sectional, p = 0.829 and longitudinal, p = 0.329) and chest CT abnormalities (p = 0.202) were not significantly different between DNAH11 and DNAH5 variants. CONCLUSION: This study suggests a genotype-phenotype correlation for some of the evaluated clinical characteristics of the two most frequently involved genes in this study, namely DNAH11 and DNAH5.

Human Genetics of Defects of Situs.

Defects of situs are associated with complex sets of congenital heart defects in which the normal concordance of asymmetric thoracic and abdominal organs is disturbed. The cellular and molecular mechanisms underlying the formation of the embryonic left-right axis have been investigated extensively in the past decade. This has led to the identification of mutations in at least 33 different genes in humans with heterotaxy and situs defects. Those mutations affect a broad range of molecular components, from transcription factors, signaling molecules, and chromatin modifiers to ciliary proteins. A substantial overlap of these genes is observed with genes associated with other congenital heart diseases such as tetralogy of Fallot and double-outlet right ventricle, d-transposition of the great arteries, and atrioventricular septal defects. In this chapter, we present the broad genetic heterogeneity of situs defects including recent human genomics efforts.

Clinical Presentation and Therapy of Anomalies of the Situs.

Situs abnormalities may occur in many and most often more complex congenital cardiac malformations. These conditions are collectively referred to as heterotaxy syndromes, derived from the Greek words "heteros" meaning different and "taxos" meaning orientation or arrangement. Clinically, heterotaxy spectrum encompasses defects in the left-right laterality and arrangement of visceral organs. "Situs" is derived from Latin and is the place where something exists or originates. In human anatomy, situs can be solitus (derived from Latin, meaning "normal"), inversus, or ambiguus. Heterotaxy syndrome represents an intermediate arrangement of internal organs between situs solitus and situs inversus, also known as "situs ambiguous." Situs ambiguus describes an abnormal distribution of major visceral organs within the chest and abdomen. The determination of situs as normal, inversus, or ambiguus is primarily based on the location of unpaired organs such as the spleen, liver, stomach, and intestines. Diagnosis is made by clinical examination, echocardiography, a chest X-ray (position of the heart, stomach, and liver), and ultrasound of the abdominal organs. Situs is considered solitus if the left atrium, spleen, stomach, and the trilobed lung are on the left side and the liver and bilobed lung are on the right side. Situs ambiguus is present if the location of unpaired structures is random or indeterminate even after detailed and appropriate imaging. Situs inversus results when the arrangement of the thoracic and abdominal organs is mirrored. Individuals with situs inversus or situs solitus do not experience fatal dysfunction of their organ systems, as general anatomy and morphology of the abdominothoracic organ-vessel systems are conserved.

Investigation of the genetic and clinical features of laterality disorders in prenatal diagnosis: discovery of a novel compound heterozygous mutation in the DNAH11 gene.

BACKGROUND: Left-right laterality disorders are a heterogeneous group of disorders caused by an altered position or orientation of the thoracic and intra-abdominal organs and vasculature across the left-right axis. They mainly include situs inversus and heterotaxy. Those disorders are complicated by cardiovascular abnormalities significantly more frequently than situs solitus. METHODS: In this study, 16 patients with a fetal diagnosis of laterality disorder with congenital heart defects (CHD) were evaluated with a single nucleotide polymorphism array (SNP-arry) combined with whole-exome sequencing (WES). RESULTS: Although the diagnostic rate of copy number variations was 0 and the diagnostic rate of WES was 6.3% (1/16), the likely pathogenic gene DNAH11 and the candidate gene OFD1 were ultimately identified. In addition, novel compound heterozygous mutations in the DNAH11 gene and novel hemizygous variants in the OFD1 gene were found. Among the combined CHD, a single atrium/single ventricle had the highest incidence (50%, 8/16), followed by atrioventricular septal defects (37.5%, 6/16). Notably, two rare cases of common pulmonary vein atresia (CPVA) were also found on autopsy. CONCLUSION: This study identified the types of CHD with a high incidence in patients with laterality disorders. It is clear that WES is an effective tool for diagnosing laterality disorders and can play an important role in future research.

Situs Inversus Totalis in a Newborn With Primary Ciliary Dyskinesia.

Respiratory distress in the newborn is associated with numerous etiologies, some common and some rare. When respiratory distress is accompanied by laterality defects, namely, situs inversus (SI), the index of suspicion for comorbid primary ciliary dyskinesia (PCD) should be raised. Primary ciliary dyskinesia is characterized by ciliary dysmotility and the accumulation of thick secretions in the airways that obstruct air and gas exchange. Neonatal clinicians should know that while PCD is definitively diagnosed in infancy or early childhood, findings suspicious for PCD should be communicated to primary care providers at discharge from the hospital to facilitate timely subspecialty involvement, diagnosis, and treatment. This article will present a case report of a term newborn with SI totalis who was later diagnosed with PCD. We will discuss epidemiology, pathophysiology, clinical manifestations, and diagnostics, followed by management strategies. Additionally, we discuss the outpatient needs and lifespan implications.

[Emergent Off-pump Coronary Artery Bypass Grafting in a Patient with Situs Inversus Totalis: Report of a Case].

Dextrocardia associated with situs inversus totalis is a rare congenital anomaly. We herein report a patient with this condition and ischemic coronay artery disease who underwent emergency surgical myocardial revascularization. A 76-year-old man was admitted to our hospital with a diagnosis of unstable angina pectoris. He had incessant ventricular fibrillation attack on the second day of hospitalization. Emergent coronary angiography revealed total obstruction of the anatomically left anterior descending and right coronary arteries, and severe stenosis in the anatomically left circumflex artery. Emergent off-pump coronary artery bypass using saphenous vein grafts was successfully performed. Intraoperatively, the main surgeon continuouly stood on the patient's right side except during anastosiso of a vein graft to the left circumflex artery. Postoperative course was almost uneventful aside from transient renal replacement and prolonged ventilation.

Radiofrequency ablation of persistent atrial fibrillation in a patient with situs inversus totalis and interrupted inferior vena cava.

INTRODUCTION: Catheter ablation of atrial fibrillation (AF) has emerged as the most effective therapy. However, rare anatomical abnormalities such as situs inversus totalis, dextrocardia, or interrupted inferior vena cava can make ablation challenging. METHODS AND RESULTS: We report a case of a 55-year-old woman with situs inversus totalis, dextrocardia, surgical atrial septal defect repair, left-sided dual chamber pacemaker in place, and symptomatic recurrent persistent AF who underwent successful pulmonary vein and posterior wall isolation by the superior access from the left internal jugular vein. CONCLUSIONS: It is a feasible and safe approach with support of transesophageal echocardiography and multiple emerging technologies.

Novel homozygous variant in ARL2BP associated with retinitis pigmentosa, situs inversus, and male infertility in a Chinese patient.

ARL2BP is a ciliary gene associated with multiple ciliopathy phenotypes. On comprehensive clinical examinations using molecular methods, we identified a Chinese patient from a consanguineous family carrying a novel homozygous variant c.22_23delAG (p.S8Lfs*10) in ARL2BP, presenting with retinitis pigmentosa (RP), situs inversus totalis, and oligozoospermia. Situs inversus and male infertility have never been reported in the same patient with ARL2BP variants; therefore, this a novel ARL2BP-associated phenotypic triad of RP, situs inversus, and male infertility. Moreover, this patient likely had olfactory dysfunction susceptibility and presented with anosmia. We found reduced patient-derived fibroblast proliferation and ciliary length. Our findings expand the genotypic spectrum and reveal abnormal cell proliferation and ciliogenesis in ARL2BP-associated patients.

Diagnostic challenge of Creutzfeldt-Jakob disease in a patient with multimorbidity: a case-report.

BACKGROUND: Creutzfeldt-Jakob disease (CJD) is a rapidly progressive and ultimately fatal neurodegenerative condition caused by prions. The clinical symptoms of CJD vary with its subtype, and may include dementia, visual hallucinations, myoclonus, ataxia, (extra)pyramidal signs and akinetic mutism. In the early course of disease however, several clinical symptoms of CJD may mimic those of co-existing morbidities. CASE PRESENTATION: We report a male in his 60s with a history of situs inversus totalis and Churg Strauss syndrome, who presented with speech fluency disturbances, neuropsychiatric symptoms and allodynia, a few months after becoming a widower. Initially presumed a bereavement disorder along with a flare-up of Churg Strauss, his symptoms gradually worsened with apraxia, myoclonic jerks and eventually, akinetic mutism. MRI revealed hyperintensities at the caudate nucleus and thalami, while the cerebrospinal fluid was positive for the 14-3-3 protein and the real-time quick test, making the diagnosis of CJD highly probable. This case illustrates the complexities that may arise in diagnosing CJD when pre-existing multimorbidity may cloud the clinical presentation. We also discuss the potential mechanisms underlying the co-occurrence of three rare conditions (situs inversus totalis, Churg Strauss syndrome, CJD) in one patient, taking into consideration the possibility of coincidence as well as common underlying factors. CONCLUSIONS: The diagnosis of CJD may be easily missed when its clinical symptoms are obscured by those of pre-existing (rare) multimorbidity. This case highlights that when the multimorbidity has neurological manifestations, an extensive evaluation remains crucial to establish the diagnosis, minimize the risk of prion-transmission and provide appropriate guidance to patients and their caregivers.

Robotic magnetic navigation-guided pulmonary vein isolation in an atrial fibrillation patient with dextrocardia situs inversus: techniques and potential advantages.

BACKGROUND: Dextrocardia with situs inversus (DSI) is a very rare congenital anomaly. Catheter manipulation and ablation of atrial fibrillation (AF) in patients with this anatomical variant is challenging for the operators. This case report presents a safe and effective AF ablation guided by the robotic magnetic navigation (RMN) system in combination with intracardiac echocardiograhy (ICE) in a patient with DSI. CASE PRESENTATION: A 64-year-old male with DSI was referred for catheter ablation of symptomatic, drug-refractory paroxysmal AF. One transseptal access was achieved via the left femoral vein under the guidance of ICE. The three-dimensional reconstruction of the left atrium and the pulmonary veins (PVs) were performed by the magnetic catheter using the CARTO and the RMN system. Then, the electroanatomic map and pre-acquired CT images were merged. Finally, bilateral circumferential ablation lines were delivered around the ipsilateral PV ostia to achieve complete PV isolation (PVI). CONCLUSIONS: This case demonstrates that AF catheter ablation under the guidance of the RMN system using ICE is feasible and safe in a patient with DSI. Moreover, the combination of these technologies broadly facilitates treatment of patients with complex anatomy, while reducing the risk of complications.

Leadless pacemaker implantation in dextrocardia with situs viscerum inversus: A case report and literature review.

Leadless pacemaker implantation (LPI) has fewer device complications and reduced chance of infection compared to conventional pacemakers. Dextrocardia with situs viscerum inversus (DC+SVI) is a rare condition, which seldom leads to cardiac complications. However, its presence poses a challenge to operators in cardiac procedures. LPI reports in DC patients are scarce. We report a case of LPI in a DC+SVI patient, followed by a brief but comprehensive literature review.

Anesthetic Management of Patients With Kartagener Syndrome: A Systematic Review of 99 Cases.

KARTAGENER SYNDROME (KS) is characterized by the triad of chronic sinusitis, bronchiectasis, and situs inversus. The mirrored anatomy and respiratory infections in patients with KS patients pose great challenges for anesthetic management. The aim of this review is to summarize published cases with the hope of helping anesthesiologists perform anesthesia in patients with KS more safely. A comprehensive literature search for all cases of anesthetic management of KS patients was performed in Pubmed, EMBASE, CNKI, and Wanfang Database. The extracted data included age, sex, type of surgery, preoperative treatment, type of anesthesia, anesthetic agents, airway management, central venous catheterization, transesophageal echocardiogram, reversal of neuromuscular blockade, adverse events during the surgery, and postoperative complications. The study authors included 82 single-case reports, 3 case series, and 1 case cohort, with a total number of 99 patients. The most common surgical procedures were thoracic surgery (51.5%), which was followed by ear, nose, and throat surgery (16.5%), and general surgery (14.5%). The preoperative treatment of the patients was reported in only 20 patients, and included antibiotics, bronchodilators, steroids, chest physiotherapy, and postural drainage. General anesthesia was performed for 85.4% of the surgeries, and regional anesthesia was performed in 14.6% of the cases. For nonthoracic surgery, an endotracheal tube was the most commonly used airway device. For thoracic surgery, a double-lumen tube was the most commonly used airway device. The intraoperative process was uneventful in most patients, and most patients recovered smoothly in the postoperative course.

Situs inversus with dextrocardia and transposition of great arteries.

Transposition of the great arteries with left ventricle outflow tract obstruction in combination with situs inversus totalis and dextrocardia is a very rare anomaly and carries high morbidity and mortality. Only few cases have been reported with this anomaly. We describe a 21-day of infant girl with transposition of the great arteries and mirror image dextrocardia and pulmonary stenosis who underwent successful neonatal arterial switch operation and left ventricle outflow tract obstruction resection following PDA stent implantation.

Biventricular repair in an infant with transposition of the great arteries and straddling of the tricuspid valve.

Biventricular repair is challenging in patients with transposition of the great arteries and straddling of the atrioventricular valves. Biventricular repair is the preferred option because of its anatomical and physiological advantages. However, in cases where biventricular repair carries operative risks that are too high or cases with unsuitable intracardiac anatomy, univentricular heart repair may have to be chosen. We report a five-month-old male patient with transposition of the great arteries, an inlet ventricular septal defect and anomalous coronary anatomy who had previously undergone a pulmonary banding operation and balloon atrial septostomy. Successful biventricular repair was performed while the patient had straddling of the tricuspid valve.

Un cas de situs inversus complet associé à une communication interventriculaire et des anomalies oculaires chez une chienne croisée de 3 ans.

A case of complete situs inversus associated with an interventricular communication and ocular abnormalities in a 3-year-old mixed-breed female dog. A 3-year-old female dog was referred for exploration of a murmur concomitant with lethargy. An echocardiogram reveals an inversion of the position of the cardiac chambers and the presence of an interventricular communication. A computed tomography examination of the thorax and abdomen highlights the known cardiac abnormalities as well as the association of a complete situs inversus. The clinical examination also reveals ocular malformations (deviation of the eyeballs and asymmetry of the fundus). This article highlights the variety of abnormalities that can be associated with the complete inversion of the organs and demonstrates that there may be variants to the more classic picture usually encountered in humans (respiratory manifestations related to Kartagener syndrome).(Translated by Dr Serge Messier).

Salivary Gland Choristoma in External Auditory Canal: A Case Report.

INTRODUCTION: Salivary gland choristomas have been described in the middle ear but tend not to involve the external auditory canal. CASE PRESENTATION: A 6-year-old boy with situs inversus totalis presented with congenital hearing loss in the left ear due to external auditory canal atresia. High resolution computed tomography of the temporal bone demonstrated a soft tissue obstruction of the external auditory canal with a normal middle ear. Histopathologically, this was a salivary gland choristoma. Post operatively the patient had a facial nerve palsy. CONCLUSION: Salivary gland choristomas of middle ear have been reported, but have not been described with external auditory canal atresia and situs inversus totalis.

[Laparoscopic cholecystectomy with common bile duct exploration in situs inversus totalis patient]. / Colecistectomía con exploración de vías biliares laparoscópica en paciente con situs inversus totalis.

We present the case of a 77-year-old male patient with a diagnosis of chronic calculous cholecystitis and choledocholithiasis, with a history of situs inversus totalis. Therefore, a laparoscopic cholecystectomy with common bile duct exploration were performed, using the "french mirror technique", with stone extraction. Patient evolved favorably. The aim of this study is to present this clinical case that is rarely reported in the world literature (only 9 cases). Its importance lies in the fact that it would be the first published clinical case report of a laparoscopic cholecystectomy and bile duct exploration with removal of the common bile duct stones in a patient with situs inversus totalis, performed in Peru.

[Laparoscopic Low-Anterior Resection for Sigmoid Colon Cancer and Rectosigmoid Adenoma in a Patient with Situs Inversus].

A 63-year-old woman, who were in a nursing house, visited our hospital with complaints of bloody stools and anemia. Some investigations were performed, CS and CT revealed her diagnosis with sigmoid colon cancer(cT3N0M0)and rectosigmoid adenoma with situs inversus(SI). Laparoscopic low-anterior resection was performed. Postoperative course was good without any complications, and she discharged our hospital at the day 7 after the operation. In surgery, we had to be conscious of mirror image and set operative equipment and operative staffs inversely from normal setting. Some previous reports suggested that some surgical process such as cutting and separating with left hand(non-dominant hand), especially at interior separation, were effective in laparoscopic surgery for SI patients. However, in our operation, we used ultrasonic coagulator with short-pitched incision with surgeon's right hand(dominant hand)instead of left-handed process, and it could be useful for laparoscopic surgery for SI patients. In intrapelvic processes, we proceeded with the surgery as usual because of the symmetric structure of intrapelvic organs. We could complete the laparoscopic low-anterior resection for SI patient with several ingenuity for operative processes.

[Laparoscopic Colectomy for a Patient with Transverse Colon Cancer in Situs Inversus Totalis].

A 74-year-old man with situs inversus totalis visited our hospital for a positive fecal occult blood. He was diagnosed with transverse colon cancer by total colonoscopy. We performed laparoscopic partial colectomy. He was discharged on the 8th postoperative day, without postoperative complications. Histopathological examination revealed well differentiated adenocarcinoma, pT1aN0M0, pStage Ⅰ. Preoperative assessment of the anatomical position and vascular malformations, using 3- dimensional computed tomography, was essential for our safe surgical conduct.

Biallelic DNAH9 mutations are identified in Chinese patients with defective left-right patterning and cilia-related complex congenital heart disease.

Defective left-right (LR) pattering results in a spectrum of laterality disorders including situs inversus totalis (SIT) and heterotaxy syndrome (Htx). Approximately, 50% of patients with primary ciliary dyskinesia (PCD) displayed SIT. Recessive variants in DNAH9 have recently been implicated in patients with situs inversus. Here, we describe six unrelated family trios and 2 sporadic patients with laterality defects and complex congenital heart disease (CHD). Through whole exome sequencing (WES), we identified compound heterozygous mutations in DNAH9 in the affected individuals of these family trios. Ex vivo cDNA amplification revealed that DNAH9 mRNA expression was significantly downregulated in these patients carrying biallelic DNAH9 mutations, which cause a premature stop codon or exon skipping. Transmission electron microscopy (TEM) analysis identified ultrastructural defects of the outer dynein arms in these affected individuals. dnah9 knockdown in zebrafish lead to the disturbance of cardiac left-right patterning without affecting ciliogenesis in Kupffer's vesicle (KV). By generating a Dnah9 knockout (KO) C57BL/6n mouse model, we found that Dnah9 loss leads to compromised cardiac function. In this study, we identified recessive DNAH9 mutations in Chinese patients with cardiac abnormalities and defective LR pattering.