Atypical Presentation and Evolution of Necrotizing Enterocolitis as a PIK3CA Pathological Variant.

Activating mutation of PIK3CA is linked with cases of overgrowth syndromes and belongs to the PIK3CA-related overgrowth spectrum (PROS). Mutations in this gene are associated with vascular malformations, brain abnormalities, and an increased risk for certain tumors. We report the case of a newborn girl, preterm at 34 weeks of gestation, referred to our center for atypical necrotizing enterocolitis (NEC). At laparotomy, the appearance of the intestinal tract was described as puffy, cauliflower-like with a dark purplish coloration. Subsequently, the colostomy was described as having a consistent proliferative appearance. Medical treatment with sirolimus resulted in minimal improvement. There are no reported cases in the literature of association between NEC and PIK3CA mutation. It is possible that PIK3CA mutation, including the related vascular anomalies, plays a role in the pathogenesis of NEC with this condition.

Combined surgery and sclerotherapy for 13 years: a case report of a patient with CLOVES.

Congenital lipomatous overgrowth, vascular malformations, epidermal nevi, and skeletal anomalies (CLOVES) constitute a rare overgrowth disorder resulting from a mosaic function-acquiring mutation in the PIK3CA gene. Targeted drugs for the PI3K-AKT signaling pathway remain under clinical trial and surgery is commonly used to meet both aesthetic and functional requirements for CLOVES patients. We report here the course and experience of a male patient treated at our institution for up to 13 years. The course of treatment consisted of nine anhydrous ethanol sclerotherapy procedures and two segmental trunk mass resections. After undergoing sequential treatment, the patient experienced improved thoracic deformity and scoliosis, enabling him to grow and develop normally.

Skeletal abnormalities in mice with Dnmt3a missense mutations.

Overgrowth and intellectual disability disorders in humans are typified by length/height and/or head circumference ≥ 2 standard deviations above the mean as well as intellectual disability and behavioral comorbidities, including autism and anxiety. Tatton-Brown-Rahman Syndrome is one type of overgrowth and intellectual disability disorder caused by heterozygous missense mutations in the DNA methyltransferase 3A (DNMT3A) gene. Numerous DNMT3A mutations have been identified in Tatton-Brown-Rahman Syndrome patients and may be associated with varying phenotype severities of clinical presentation. Two such mutations are the R882H and P904L mutations which result in severe and mild phenotypes, respectively. Mice with paralogous mutations (Dnmt3aP900L/+ and Dnmt3aR878H/+) exhibit overgrowth in their long bones (e.g., femur, humerus), but the mechanisms responsible for their skeletal overgrowth remain unknown. The goal of this study is to characterize skeletal phenotypes in mouse models of Tatton-Brown-Rahman Syndrome and identify potential cellular mechanisms involved in the skeletal overgrowth phenotype. We report that mature mice with the Dnmt3aP900L/+ or Dnmt3aR878H/+ mutation exhibit tibial overgrowth, cortical bone thinning, and weakened bone mechanical properties. Dnmt3aR878H/+ mutants also contain larger bone marrow adipocytes while Dnmt3aP900L/+ mutants show no adipocyte phenotype compared to control animals. To understand the potential cellular mechanisms regulating these phenotypes, growth plate chondrocytes, osteoblasts, and osteoclasts were assessed in juvenile mutant mice using quantitative static histomorphometry and dynamic histomorphometry. Tibial growth plates appeared thicker in mutant juvenile mice, but no changes were observed in osteoblast activity or osteoclast number in the femoral mid-diaphysis. These studies reveal new skeletal phenotypes associated with Tatton-Brown-Rahman Syndrome in mice and provide a rationale to extend clinical assessments of patients with this condition to include bone density and quality testing. These findings may be also informative for skeletal characterization of other mouse models presenting with overgrowth and intellectual disability phenotypes.

Molecular characterization of 13 patients with PIK3CA-related overgrowth spectrum using a targeted deep sequencing approach.

Activating variants in the PIK3CA gene cause a heterogeneous spectrum of disorders that involve congenital or early-onset segmental/focal overgrowth, now referred to as PIK3CA-related overgrowth spectrum (PROS). Historically, the clinical diagnoses of patients with PROS included a range of distinct syndromes, including CLOVES syndrome, dysplastic megalencephaly, hemimegalencephaly, focal cortical dysplasia, Klippel-Trenaunay syndrome, CLAPO syndrome, fibroadipose hyperplasia or overgrowth, hemihyperplasia multiple lipomatosis, and megalencephaly capillary malformation-polymicrogyria (MCAP) syndrome. MCAP is a sporadic overgrowth disorder that exhibits core features of progressive megalencephaly, vascular malformations, distal limb malformations, cortical brain malformations, and connective tissue dysplasia. In 2012, our research group contributed to the identification of predominantly mosaic, gain-of-function variants in PIK3CA as an underlying genetic cause of the syndrome. Mosaic variants are technically more difficult to detect and require implementation of more sensitive sequencing technologies and less stringent variant calling algorithms. In this study, we demonstrated the utility of deep sequencing using the Illumina TruSight Oncology 500 (TSO500) sequencing panel in identifying variants with low allele fractions in a series of patients with PROS and suspected mosaicism: pathogenic, mosaic PIK3CA variants were identified in all 13 individuals, including 6 positive controls. This study highlights the importance of screening for low-level mosaic variants in PROS patients. The use of targeted panels with deep sequencing in clinical genetic testing laboratories would improve diagnostic yield and accuracy within this patient population.

An adult patient with Tatton-Brown-Rahman syndrome caused by a novel DNMT3A variant and axonal polyneuropathy.

Tatton-Brown-Rahman syndrome (TBRS) is a rare autosomal dominant overgrowth syndrome first reported in 2014 and caused by pathogenic variants in the DNA methyltransferase 3A (DNMT3A) gene. All individuals reported to date share a phenotype of somatic overgrowth, dysmorphic features, and intellectual disability. Peripheral neuropathy was not described in these cases. We report an adult patient with TBRS caused by a novel pathogenic DNMT3A variant (NM_175629.2: c.2036G>A, p.(Arg688His)) harboring an axonal length-dependent sensory-motor polyneuropathy. Extensive laboratory and molecular genetic work-up failed to identify alternative causes for this patient's neuropathy. We propose that axonal neuropathy may be a novel, age-dependent phenotypic feature in adults with TBRS and suggest that this syndrome should be considered in the differential diagnosis of patients with overgrowth, cognitive and psychiatric difficulties, and peripheral neuropathy.

Early is Better: Report of a Cowden Syndrome.

In the clinical practice, it is not common for pediatricians to visit children with overgrowth phenotype. When it happens, it is important to focus on the age of manifestations and research the pathogenic causes using appropriate genetic test. Cowden syndrome is one of these rare causes; it is an autosomal dominant genodermatosis characterized by multiple hamartomas of ectodermal, mesodermal, and endodermal origin. It is caused by loss of function mutations in the phosphatase and tensin homolog (PTEN) gene located on chromosome 10q23.1 Loss of function of the PTEN gene contributes to overgrowth and risk for a variety of cancers including breast, thyroid, endometrium, skin, kidneys, and colon. The early diagnosis of Cowden disease allows a careful monitoring of the patients who are facing the risk of cancer transformation, which is the principal complication of the condition.

Case report: Progressive pulmonary artery hypertension in a case of megalencephaly-capillary malformation syndrome.

Megalencephaly-capillary malformation syndrome (MCAP, OMIM # 602501) is caused by hyperactivity of the thephosphoinositide-3-kinase (PI3K)-Vakt murine thymoma viral oncogene homolog (AKT)-mammalian target of rapamycin (mTOR) pathway, which results in megalencephaly, capillary malformations, asymmetrical overgrowth, and connective tissue dysplasia. Herein, we report the case of a 7-month-old girl with MCAP due to a PIK3CA somatic mosaic variant who presented with atrial tachycardia, finally diagnosed as pulmonary arterial hypertension (PAH). Oxygen therapy and sildenafil decreased pulmonary blood pressure and improved atrial tachycardia. Previous studies reported an association between the PI3K/AKT/mTOR pathway and abnormal pulmonary arterial smooth muscle cell proliferation, which may be associated with PAH. PAH should be considered a potentially lethal complication in MCAP patients, even when no structural cardiac abnormalities are identified in the neonatal period.

Report on a Case with Moreno-Nishimura-Schmidt Overgrowth Syndrome: A Clinically Delineated Disease Yet of an Unknown Origin!

Introduction: Overgrowth syndromes are a heterogeneous group of genetic disorders characterized by excessive growth, often accompanied by additional clinical features, such as facial dysmorphism, hormonal imbalances, cognitive impairment, and increased risk for neoplasia. Moreno-Nishimura-Schmidt (M-N-S) overgrowth syndrome is a very rare overgrowth syndrome characterized by severe pre- and postnatal overgrowth, dysmorphic facial features, kyphoscoliosis, large hands and feet, inguinal hernia, and distinctive skeletal features. The clinical and radiological features of the disorder have been well delineated, yet its molecular pathogenesis remains unclear. Case Presentation: We report on a Lebanese boy with M-N-S syndrome, whose clinical manifestations were compared with those of previously reported 5 affected individuals. Whole-exome sequencing combined with comparative genome hybridization analysis failed to delineate the molecular basis of the phenotype. However, epigenetic studies revealed a different methylation status of several CpG sites between him and healthy controls, with methyltransferase activity showing the most significant enrichment. Conclusion: An additional case of M-N-S syndrome recapitulated the clinical and radiological manifestations described in the previous reports. The data in the epigenetic studies implicated that abnormal methylations might play an essential role in development of the disease phenotype. However, additional studies in a clinically homogeneous cohort of patients are crucial to confirm this hypothesis.

Vascular Anomalies Care in the United States: A Cross-Sectional National Survey.

OBJECTIVE: To characterize the current distribution, composition, and practice patterns of multidisciplinary vascular anomalies (VAs) teams in the US. STUDY DESIGN: This is a cross-sectional survey of children's hospitals in the US offering VAs care. We approached 142 children's hospitals that provided care for VAs via email. The survey evaluated VA clinic location, medical staffing, research participation, and treatments offered. The survey was administered between October 2021 and July 2022. RESULTS: Participants from 95 eligible hospitals responded to the survey (response rate = 67%). Large areas of the Midwest and Northwest US had no available multidisciplinary VA teams or clinics. Most respondents worked at academic centers (89%), with 66% at a freestanding children's hospital, and 56% reported having a multidisciplinary clinic. Most common physician participants in clinic included hematology-oncology (91%), interventional radiology (87%), dermatology (85%), plastic surgery (81%), and otolaryngology (74%). Only 38% of programs included medical geneticists. Smaller hospitals had fewer medical and ancillary staff and offered fewer therapeutic options. Research was available at most larger institutions (69%) but less commonly at smaller hospitals (34%). CONCLUSIONS: Major portions of the US lack multidisciplinary VA care. Furthermore, VA programs vary in composition and geneticists are absent from the majority of programs. These findings should inform efforts to address disparate access and develop standards of care for multidisciplinary VA care in the US.

Contemporary management of extracranial vascular malformations.

Vascular malformations are congenital vascular anomalies that originate because of disorganized angiogenesis, most commonly from spontaneous somatic genetic mutations. The modern management of vascular malformations requires a multidisciplinary team that offers patients the gamut of medical, surgical, and percutaneous treatment options with supportive care. This manuscript discusses the standard and contemporary management strategies surrounding extracranial vascular malformations and overgrowth syndromes.

A rare case of Klippel-Trenaunay syndrome presenting with chronic myeloid leukemia.

BACKGROUND: Klippel-Trenaunay syndrome (KTS) is an overgrowth syndrome associated with capillary/venous/ lymphatic malformations with limb hypertrophy and cancer risk. Various cancers, mostly Wilms tumor, have been reported in patients with KTS, but not leukemia. Chronic myeloid leukemia (CML) is also a rare disease in children, where there is no known disease or syndrome to predispose to CML. CASE: We report a case of CML incidentally diagnosed in a child with KTS when he was bleeding from surgery of the left groin for vascular malformation. CONCLUSIONS: This case reflects the variety of cancer types that may accompany KTS and provides information about CML prognosis in such patients.

Imagawa-Matsumoto syndrome: SUZ12-related overgrowth disorder.

The SUZ12 gene encodes a subunit of polycomb repressive complex 2 (PRC2) that is essential for development by silencing the expression of multiple genes. Germline heterozygous variants in SUZ12 have been found in Imagawa-Matsumoto syndrome (IMMAS) characterized by overgrowth and multiple dysmorphic features. Similarly, both EZH2 and EED also encode a subunit of PRC2 each and their pathogenic variants cause Weaver syndrome and Cohen-Gibson syndrome, respectively. Clinical manifestations of these syndromes significantly overlap, although their different prevalence rates have recently been noted: generalized overgrowth, intellectual disability, scoliosis, and excessive loose skin appear to be less prevalent in IMMAS than in the other two syndromes. We could not determine any apparent genotype-phenotype correlation in IMMAS. The phenotype of neurofibromatosis type 1 arising from NF1 deletion was also shown to be modified by the deletion of SUZ12, 560 kb away. This review deepens our understanding of the clinical and genetic characteristics of IMMAS together with other overgrowth syndromes related to PRC2. We also report on a novel IMMAS patient carrying a splicing variant (c.1023+1G>C) in SUZ12. This patient had a milder phenotype than other previously reported IMMAS cases, with no macrocephaly or overgrowth phenotypes, highlighting the clinical variation in IMMAS.

Approach to clinically significant vascular anomalies in children.

Vascular anomalies consist of tumours or malformations made up of abnormal growth or collections of blood vessels that can result in functional or cosmetic problems. While many vascular anomalies are present at birth, some do not appear until later in life, making diagnosis more challenging. Although many vascular anomalies are benign, some are associated with serious complications and may involve multiple organ systems. This article highlights the important features of clinically significant vascular anomalies to help physicians promptly identify and refer these cases to a specialised multidisciplinary team for evaluation and management. The discussion includes the various presenting complaints of vascular anomalies in children, namely, rapidly growing birthmarks, painful lesions, seizures/neurological manifestations, bleeding diathesis, cardiac/airway abnormalities and part of an overgrowth syndrome.

A Rare Case of an Asymmetric Overgrowth Syndrome in a Kenyan African Child: A Case Report and Review of Literature.

Body overgrowth may be generalized or may affect certain areas. We present a seven-year-old African male with progressive, asymmetric, postnatal overgrowth of the left side of his face and left upper limb. The impression of proteus syndrome (PS) was made based on established clinical diagnostic criteria presented in the literature. Our objective is to highlight the diagnosis based on clinical features, investigations, and a multidisciplinary approach to the management of proteus syndrome.

Gastrointestinal toxicity of systemic oncology immunotherapy.

BACKGROUND: Systemic anti-cancer immunotherapy provides a substantial progress in options of current oncology treatment. Yet, this therapeutic approach is potentially associated with a significant gastrointestinal toxicity. AIM: The purpose of this paper is to provide a comprehensive review on pathogenesis, clinical features, dia gnostics and therapy of these toxicities. Review of current knowledge: Check-point inhibitors brought a major progress in anti-cancer immunotherapy and improved significantly prognosis of several malignancies (e. g. metastatic malignant melanoma, non-small-cell lung cancer, gastric and colorectal cancers in high-risk population associated with presence of pathogenic mutations, renal cell carcinoma, squamous cell carcinoma of the head and neck and urothelial carcinoma). They include monoclonal antibodies targeting cytotoxic T lymphocyte-associated antigen 4 (CTLA4; e. g. ipilimumab, tremelimumab), programmed death-1 receptor (PD-1; e. g. pembrolizumab, nivolumab) and its ligand PD-L1 (e. gatezolizumab, avelumab). Chimeric antigen receptor (CAR) T-cell therapy is another new option for haematological malignancies and metastatic colorectal cancer. Major symptoms of gastrointestinal toxicity caused by systemic immunotherapy include diarrhoea (20-50%), entero-colitis (1-10%) and laboratory or clinical signs of hepatopathy (~10%). Anti-cancer immunotherapy can be also complicated by infections (Clostridium difficile, Mycoplasma and/ or cytomegalovirus). There is no data on other possible complications so far. However, it can be assumed that these will also include bile acid malabsorption as well as small intestinal bacterial overgrowth syndrome. Treatment of gastrointestinal complications of immunotherapy should be graded according to their severity. It includes symptomatic medications (e. g. loperamide), systemic glucocorticoids and anti-TNF monoclonal antibodies (alone or together with mycofenolate mofetil or tacrolimus in the most severe cases). CONCLUSIONS: Awareness of possible complications of systemic anti-cancer immunotherapy is crucial for patients safety. It is mandatory to consider immune-related adverse events, complicating infections, bile acids malabsorption and small intestinal bacterial overgrowth syndrome. Prompt proper dia gnostics and immediate vigorous therapy infl uence the outcome of patients signifi cantly. A strictly individualized approach is indispensable.

Clinical and genetic analyses of patients with lateralized overgrowth.

BACKGROUND: The genetic features and treatment strategies of lateralized overgrowth have been elusive. We performed this study to analyze the genetic characteristics and treatment results of propranolol- or alpelisib-treated patients with lateralized overgrowth. METHODS: Fifteen patients with lateralized overgrowth were involved. Clinical characteristics and whole-body magnetic resonance imaging (WB-MRI) findings were evaluated. Targeted exome sequencing with a gene panel of affected tissue and peripheral white blood cells was performed. Propranolol was administered and treatment results were evaluated. The PIK3CA inhibitor alpelisib was prescribed via a managed access program. RESULTS: The identified mutations were PIK3CA (n = 7), KRAS (n = 2), PTEN (n = 1), MAP2K3 (n = 1), GNAQ (n = 1), TBC1D4 (n = 1), and TEK (n = 1). Propranolol was prescribed in 12 patients, and 7 experienced mild improvement of symptoms. Alpelisib was prescribed in two patients with a PIK3CA mutation, and the reduction of proliferated masses after 1 year of treatment was proved by WB-MRI. CONCLUSIONS: Targeted exome sequencing identified various genetic features of lateralized overgrowth. Propranolol could be applied as an adjuvant therapy for reducing vascular symptoms, but a PIK3CA inhibitor would be the primary therapeutic strategy for PIK3CA-related overgrowth syndrome.

The Role of Interventional Pain Management in Proteus Syndrome: A Case Report.

Proteus syndrome (PS) is a rare overgrowth disease process with only a few hundred cases being reported in the literature. Abnormal formation of the vertebral bodies causing scoliosis and spinal stenosis are common features that lead to debilitating pain in these patients. We present a case of a 35-year-old male landscaper with a history of PS causing severe scoliosis and vertebral overgrowth who underwent recurrent sets of multilevel zygapophyseal joint injections for management of his axial back pain. This case illustrates the utility of interventional spinal procedures in patients with progressive pain from PS.

Severe small intestinal bacterial overgrowth syndrome after jejunal feeding requiring surgical intervention: a case report and review of the literature.

BACKGROUND: Small intestinal bacterial overgrowth (SIBO) is a condition of unknown prevalence characterized by an excessive amount of bacteria in the small bowel, typically resulting in vague gastrointestinal symptoms with bloating being most commonly reported. Here we describe a severe case of SIBO leading to small bowel necrosis requiring surgical intervention. CASE PRESENTATION: A 55-year-old Hispanic female with gastric outlet obstruction secondary to a newly diagnosed gastric adenocarcinoma, receiving neoadjuvant chemotherapy, developed bloody gastrostomy output and rapidly progressing nausea and abdominal distention 3 days after jejunostomy tube placement and initiation of jejunal enteral nutrition. Imaging revealed diffuse pneumatosis and portal venous gas. Surgical exploration confirmed segmental bowel necrosis requiring resection. Histologic findings were consistent with SIBO. CONCLUSIONS: Presentation of severe SIBO in the setting of intestinal stasis secondary to gastric outlet after initiation of enteral feeds is a rare phenomenon. Early recognition and diagnosis of SIBO is critical in minimizing patient morbidity and mortality.

[Assessment of the state of the small intestine microbiota in children on a long-term dairy-free diet].

An overview of recent outcomes of studies indicates an imbalance in the diet of children. Quantitative and qualitative malnutrition of children is the basis of a number of childhood diseases. The aim of the research was to study the prevalence of small intestine bacterial overgrowth syndrome (SIBO) in children on a long-term dairy-free diet. Material and methods. 40 children aged 7-11 years following a long-term dairy-free diet (average 3 years and 5 months, from 0.5 to 6.3 years) were examined (main group). 30 children who did not follow restrictive diets were consisted control group. In all children, SIBO was determined using a hydrogen breath test with a load of lactulose using a digital analyzer of exhaled hydrogen. Results. The proportion of children with intolerance to dairy products was 32.5%: 10.0% with allergy to cow's milk proteins, and 22.5% with lactose intolerance. 27.5% children followed a dairy-free diet according to an unjustified prescription by physician. 30.0% of children did not consume dairy products because of their unwillingness. 10.0% of children did not consume dairy products due to the unwillingness of their parents. An imbalance in the microbiota of the small intestine during the hydrogen breath test with lactulose loading was detected in 55.0% of children following a long-term dairy-free diet. 22.5% of children complained of recurrent abdominal pain, diarrhea was determined in 10.0%, constipation - in 7.5%, nausea - in 10.0%. In the control group, the SIBO during the hydrogen breath test with lactulose loading was found in 20.0%. Periodic abdominal pain was determined in 10.0%, nausea - in 6.7%, diarrhea - in 10.0%, constipation - in 3.3% children. Conclusion. Thus, among children of primary school age who follow a long-term dairyfree diet, SIBO is significantly more often recorded relative to children who are on a traditional type of diet.