Progressive liver, kidney, and heart degeneration in children and adults affected by TULP3 mutations.

Organ fibrosis is a shared endpoint of many diseases, yet underlying mechanisms are not well understood. Several pathways governed by the primary cilium, a sensory antenna present on most vertebrate cells, have been linked with fibrosis. Ciliopathies usually start early in life and represent a considerable disease burden. We performed massively parallel sequencing by using cohorts of genetically unsolved individuals with unexplained liver and kidney failure and correlated this with clinical, imaging, and histopathological analyses. Mechanistic studies were conducted with a vertebrate model and primary cells. We detected bi-allelic deleterious variants in TULP3, encoding a critical adaptor protein for ciliary trafficking, in a total of 15 mostly adult individuals, originating from eight unrelated families, with progressive degenerative liver fibrosis, fibrocystic kidney disease, and hypertrophic cardiomyopathy with atypical fibrotic patterns on histopathology. We recapitulated the human phenotype in adult zebrafish and confirmed disruption of critical ciliary cargo composition in several primary cell lines derived from affected individuals. Further, we show interaction between TULP3 and the nuclear deacetylase SIRT1, with roles in DNA damage repair and fibrosis, and report increased DNA damage ex vivo. Transcriptomic studies demonstrated upregulation of profibrotic pathways with gene clusters for hypertrophic cardiomyopathy and WNT and TGF-ß signaling. These findings identify variants in TULP3 as a monogenic cause for progressive degenerative disease of major organs in which affected individuals benefit from early detection and improved clinical management. Elucidation of mechanisms crucial for DNA damage repair and tissue maintenance will guide novel therapeutic avenues for this and similar genetic and non-genomic diseases.

Molecular genetic diagnosis of kidney ciliopathies: Lessons from interpreting genomic sequencing data and the requirement for accurate phenotypic data.

INTRODUCTION: Massively parallel sequencing (MPS) techniques have made a major impact on the identification of the genetic basis of inherited kidney diseases such as the ciliopathy autosomal dominant polycystic kidney disease (ADPKD). Great care must be taken when analysing MPS data in isolation from accurate phenotypic information, as this can cause misdiagnosis. METHODS: Here, we describe a family trio, recruited to the Genomics England 100,000 Genomes Project, labelled as having cystic kidney disease, who were genetically unsolved following routine data analysis pipelines. We performed a bespoke reanalysis of Whole Genome Sequencing (WGS) data and coupled this with revised phenotypic data and targeted PCR and Sanger sequencing to provide a precise molecular genetic diagnosis. RESULTS: We detected a heterozygous PKD1 frameshift variant within the WGS data which segregated with the redefined ADPKD phenotypes. An additional heterozygous exon deletion in ALG8 was also found in affected and unaffected individuals, but its precise clinical significance remains unclear. CONCLUSION: This case illustrates that reanalysis of WGS data in unsolved cases of cystic kidney disease is valuable. Clinical phenotypes must be reassessed as these may have been incorrectly recorded and evolve over time. Undertaking additional studies including genotype-phenotype correlation in wider family members provides useful diagnostic information.

Mouse genetics reveals Barttin as a genetic modifier of Joubert syndrome.

Genetic and phenotypic heterogeneity and the lack of sufficiently large patient cohorts pose a significant challenge to understanding genetic associations in rare disease. Here we identify Bsnd (alias Barttin) as a genetic modifier of cystic kidney disease in Joubert syndrome, using a Cep290-deficient mouse model to recapitulate the phenotypic variability observed in patients by mixing genetic backgrounds in a controlled manner and performing genome-wide analysis of these mice. Experimental down-regulation of Bsnd in the parental mouse strain phenocopied the severe cystic kidney phenotype. A common polymorphism within human BSND significantly associates with kidney disease severity in a patient cohort with CEP290 mutations. The striking phenotypic modifications we describe are a timely reminder of the value of mouse models and highlight the significant contribution of genetic background. Furthermore, if appropriately managed, this can be exploited as a powerful tool to elucidate mechanisms underlying human disease heterogeneity.

Biallelic variants in TTC21B as a rare cause of early-onset arterial hypertension and tubuloglomerular kidney disease.

Monogenic disorders of the kidney typically affect either the glomerular or tubulointerstitial compartment producing a distinct set of clinical phenotypes. Primary focal segmental glomerulosclerosis (FSGS), for instance, is characterized by glomerular scarring with proteinuria and hypertension while nephronophthisis (NPHP) is associated with interstitial fibrosis and tubular atrophy, salt wasting, and low- to normal blood pressure. For both diseases, an expanding number of non-overlapping genes with roles in glomerular filtration or primary cilium homeostasis, respectively, have been identified. TTC21B, encoding IFT139, however has been associated with disorders of both the glomerular and tubulointerstitial compartment, and linked with defective podocyte cytoskeleton and ciliary transport, respectively. Starting from a case report of extreme early-onset hypertension, proteinuria, and progressive kidney disease, as well as data from the Genomics England 100,000 Genomes Project, we illustrate here the difficulties in assigning this mixed phenotype to the correct genetic diagnosis. Careful literature review supports the notion that biallelic, often hypomorph, missense variants in TTC21B are commonly associated with early-onset hypertension and histological features of both FSGS and NPHP. Increased clinical recognition of this mixed glomerular and tubulointerstitial disease with often mild or absent features of a typical ciliopathy as well as inclusion of TTC21B on gene panels for early-onset arterial hypertension might shorten the diagnostic odyssey for patients affected by this rare tubuloglomerular kidney disease.

Paraneoplastic cast nephropathy associated with malignant prolactinoma: A case report and literature review.

Malignant prolactinomas are very rare and are diagnosed when a prolactin-producing pituitary adenoma has metastasized. We report on a 54-year-old man with a history of macroprolactinoma transforming into a pituitary carcinoma secreting both prolactin and growth hormone with metastases to the stomach, bone, lungs, retroperitoneum, and kidney. Reviewing the literature, this case is the first reporting of a pituitary carcinoma with biopsy-proven paraneoplastic cast nephropathy. Symptoms and renal function improved following a course of palliative chemotherapy and radiotherapy. After 2 years, his disease progressed requiring further palliative treatment that was complicated by severe chest sepsis. He was not fit for further chemotherapy, receiving symptomatic relief in a hospice, and died soon after. The case highlights the importance of considering a patient's past medical history in the context of persistent unexplained renal impairment and systemic metastases when unexplained systemic symptoms and multi-organ involvement is present. The importance of renal biopsy for definitive diagnosis and before using potentially nephrotoxic chemotherapy is also highlighted. Renal diagnosis helped inform the decision to give chemotherapy, with the importance of this evidenced by an improvement in renal function following chemotherapy.

Preclinical evaluation of the first intravenous small molecule MDM2 antagonist alone and in combination with temozolomide in neuroblastoma.

High-risk neuroblastoma, a predominantly TP53 wild-type (wt) tumour, is incurable in >50% patients supporting the use of MDM2 antagonists as novel therapeutics. Idasanutlin (RG7388) shows in vitro synergy with chemotherapies used to treat neuroblastoma. This is the first study to evaluate the in vivo efficacy of the intravenous idasanutlin prodrug, RO6839921 (RG7775), both alone and in combination with temozolomide in TP53 wt orthotopic neuroblastoma models. Detection of active idasanutlin using liquid chromatography-mass spectrometry and p53 pathway activation by ELISA assays and Western analysis showed peak plasma levels 1 h post-treatment with maximal p53 pathway activation 3-6 h post-treatment. RO6839921 and temozolomide, alone or in combination in mice implanted with TP53 wt SHSY5Y-Luc and NB1691-Luc cells showed that combined RO6839921 and temozolomide led to greater tumour growth inhibition and increase in survival compared to vehicle control. Overall, RO6839921 had a favourable pharmacokinetic profile consistent with intermittent dosing and was well tolerated alone and in combination. These preclinical studies support the further development of idasanutlin in combination with temozolomide in neuroblastoma in early phase clinical trials.

Thrombotic Microangiopathy in Inverted Formin 2-Mediated Renal Disease.

The demonstration of impaired C regulation in the thrombotic microangiopathy (TMA) atypical hemolytic uremic syndrome (aHUS) resulted in the successful introduction of the C inhibitor eculizumab into clinical practice. C abnormalities account for approximately 50% of aHUS cases; however, mutations in the non-C gene diacylglycerol kinase-ε have been described recently in individuals not responsive to eculizumab. We report here a family in which the proposita presented with aHUS but did not respond to eculizumab. Her mother had previously presented with a post-renal transplant TMA. Both the proposita and her mother also had Charcot-Marie-Tooth disease. Using whole-exome sequencing, we identified a mutation in the inverted formin 2 gene (INF2) in the mutational hotspot for FSGS. Subsequent analysis of the Newcastle aHUS cohort identified another family with a functionally-significant mutation in INF2 In this family, renal transplantation was associated with post-transplant TMA. All individuals with INF2 mutations presenting with a TMA also had aHUS risk haplotypes, potentially accounting for the genetic pleiotropy. Identifying individuals with TMAs who may not respond to eculizumab will avoid prolonged exposure of such individuals to the infectious complications of terminal pathway C blockade.

Cutaneous B-lymphoblastic lymphoma with IL3/IgH translocation presenting with hypereosinophilia and acute endocarditis.

Hypereosinophilia is a rare phenomenon associated with childhood malignancy, predominantly acute lymphoblastic leukaemia. Causation is unclear and likely to have multiple mechanisms. We report a six year old boy presenting with hypereosinophilia and associated Loeffler endocarditis. Three months following his initial hypereosinophilia he developed cutaneous B-lymphoblastic lymphoma. Re-analysis of apparently uninvolved bone marrow, taken at initial presentation, revealed a single, previously unidentified, t(5;14)(q31;q32) positive cell. Using fluorescent in situ hybridisation, we demonstrate IL3/IgH@ fusion in cutaneous lymphoma cells. Our case confirms the association of hypereosinophilia and B-lymphoblastic lymphoma and strengthens the association between IL3 hypersecretion and hypereosinophilia.

Utility of echocardiography in identifying right ventricular extension of Wilm's tumor.

We present a rare case of a child with a Wilm's tumor with an intravascular tumor-thrombus extending from the inferior vena cava to the right ventricle via the tricuspid valve. Rapid tumor progression resulted in life-threatening clinical deterioration. Radiologic and cardiac imaging demonstrated the extent of the intravascular extension of her tumor-thrombus. Emergency neo-adjuvant chemotherapy resulted in rapid clinical improvement, so that complete surgical excision was possible. Following multimodality therapy, the child is now in remission. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 43:262-264, 2015.

Evaluation of treatment outcome in 175 patients with Hodgkin lymphoma aged 60 years or over: the SHIELD study.

The SHIELD program for Hodgkin lymphoma in patients 60 years of age or older, prospectively evaluated clinical features and outcome in a large patient cohort (n = 175). The central element was a phase 2 study of VEPEMB chemotherapy (n = 103, median age 73 years) incorporating comorbidity assessment. A total of 72 other patients were treated off-study but registered prospectively and treated concurrently with: ABVD (n = 35); CLVPP (n = 19), or other (n = 18). Of VEPEMB patients, 31 had early-stage disease (stage 1A/2A) and received VEPEMB 3 times plus radiotherapy. Median follow-up was 36 months. Complete remission (CR) rate (intention-to-treat) was 74% and 3-year overall survival (OS) and progression-free survival (PFS) were 81% and 74%, respectively. A total of 72 patients had advanced-stage disease (stage 1B/2B/3 or 4) and received VEPEMB 6 times. CR rate was 61% with 3-year OS and PFS of 66% and 58%, respectively. Of patients achieving CR, 13% with early-stage and 5% with advanced-stage disease progressed. Overall treatment-related mortality was 7%. In patients treated with curative intent with VEPEMB, ABVD, and CLVPP (n = 157), CR linked to several factors in univariate analysis. In a Cox regression model only, obtaining CR remained significant for OS and CR plus comorbidity and age for PFS. RS-EBV status had no significant effect on outcome.

Diverse retinal-kidney phenotypes associated with NPHP1 homozygous whole-gene deletions in patients with kidney failure.

A precise diagnosis in medicine allows appropriate disease-specific management. Kidney failure of unknown aetiology remains a frequent diagnostic label within the haemodialysis unit and kidney transplant clinic, accounting for 15-20% of these patients. Approximately 10% of such cases may have an underlying monogenic cause of kidney failure. Modern genetic approaches can provide a precise diagnosis for patients and their families. A search for extra-renal disease manifestations is also important as this may point to a specific genetic diagnosis. Here, we present two patients where molecular genetic testing was performed because of kidney failure of unknown aetiology and associated retinal phenotypes. The first patient reached kidney failure at 16 years of age but only presented with a retinal phenotype at 59 years of age and was found to have evidence of rod-cone dystrophy. The second patient presented with childhood kidney failure at the age of 15 years and developed visual difficulties and photophobia at the age of 32 years and was diagnosed with cone dystrophy. In both cases, genetic tests were performed which revealed a homozygous whole-gene deletion of NPHP1-encoding nephrocystin-1, providing the unifying diagnosis of Senior-Løken syndrome type 1. We conclude that reviewing kidney and extra-renal phenotypes together with targeted genetic testing was informative in these cases of kidney failure of unknown aetiology and associated retinal phenotypes. The involvement of an interdisciplinary team is advisable when managing such patients and allows referral to other relevant specialities. The long time lag and lack of diagnostic clarity and clinical evaluation in our cases should encourage genetic investigations for every young patient with unexplained kidney failure. For these and similar patients, a more timely genetic diagnosis would allow for improved management, a risk assessment of kidney disease in relatives, and the earlier identification of extra-renal disease manifestations. Supplementary Information: The online version contains supplementary material available at 10.1007/s44162-024-00031-4.

Genotype/phenotype correlations in complement factor H deficiency arising from uniparental isodisomy.

We report a male infant who presented at 8 months of age with atypical hemolytic uremic syndrome (aHUS) responsive to plasma therapy. Investigation showed him to have complement factor H (CFH) deficiency associated with a homozygous CFH mutation (c.2880delT [p.Phe960fs]). Mutation screening of the child's parents revealed that the father was heterozygous for this change but that it was not present in his mother. Chromosome 1 uniparental isodisomy of paternal origin was confirmed by genotyping chromosome 1 SNPs. CD46 SNP genotyping was undertaken in this individual and another patient with CFH deficiency associated with chromosome 1 uniparental isodisomy. This showed a homozygous aHUS risk haplotype (CD46GGAAC) in the patient with aHUS and a homozygous glomerulonephritis risk haplotype (CD46AAGGT) in the patient with endocapillary glomerulonephritis. We also showed that FHL-1 (factor H-like protein 1) was present in the patient with aHUS and absent in the patient with glomerulonephritis. This study emphasizes that modifiers such as CD46 and FHL-1 may determine the kidney phenotype of patients who present with homozygous CFH deficiency.

Anti-neutrophil cytoplasmic antibody (ANCA) associated small-vessel vasculitis in a patient with diabetic nephropathy and autoimmune polyendocrinopathy syndrome (APS) Type 2: a case report.

We present a 42-year-old woman with pre-existing autoimmune polyendocrinopathy syndrome (APS) Type 2 and chronic kidney disease due to Type 1 diabetic nephropathy, who developed a rapid deterioration in renal function due to perinuclear anti-neutrophil cytoplasmic antibody (pANCA)-associated vasculitis. Although possibly a chance occurrence, ANCA have been detected more frequently in patients with a history of certain autoimmune diseases. Such an association may simply reflect an underlying tendency to immune system dysfunction in these patients and the finding of positive ANCA serology does not reliably herald the development of ANCA-associated vasculitis. However, our case illustrates that positive ANCA serology in such circumstances is not always a benign phenomenon and should still be interpreted within the clinical context. Moreover, clinicians managing patients with pre-existing autoimmune disease should maintain a low threshold for appropriate assessment should such patients develop evidence suggestive of vasculitis.

Genomic abnormalities of TP53 define distinct risk groups of paediatric B-cell non-Hodgkin lymphoma.

Children with B-cell non-Hodgkin lymphoma (B-NHL) have an excellent chance of survival, however, current clinical risk stratification places as many as half of patients in a high-risk group receiving very intensive chemo-immunotherapy. TP53 alterations are associated with adverse outcome in many malignancies; however, whilst common in paediatric B-NHL, their utility as a risk classifier is unknown. We evaluated the clinical significance of TP53 abnormalities (mutations, deletion and/or copy number neutral loss of heterozygosity) in a large UK paediatric B-NHL cohort and determined their impact on survival. TP53 abnormalities were present in 54.7% of cases and were independently associated with a significantly inferior survival compared to those without a TP53 abnormality (PFS 70.0% vs 100%, p < 0.001, OS 78.0% vs 100%, p = 0.002). Moreover, amongst patients clinically defined as high-risk (stage III with high LDH or stage IV), those without a TP53 abnormality have superior survival compared to those with TP53 abnormalities (PFS 100% vs 55.6%, p = 0.005, OS 100% vs 66.7%, p = 0.019). Biallelic TP53 abnormalities were either maintained from the presentation or acquired at progression in all paired diagnosis/progression Burkitt lymphoma cases. TP53 abnormalities thus define clinical risk groups within paediatric B-NHL and offer a novel molecular risk stratifier, allowing more personalised treatment protocols.

Percentage tumor necrosis following chemotherapy in neuroblastoma correlates with MYCN status but not survival.

The percentage of chemotherapy-induced necrosis in primary tumors corresponds with outcome in several childhood malignancies, including high-risk metastatic diseases. In this retrospective pilot study, the authors assessed the importance of postchemotherapy necrosis in high-risk neuroblastoma with a histological and case notes review of surgically resected specimens. The authors reviewed all available histology of 31 high-risk neuroblastoma cases treated with COJEC (dose intensive etoposide and vincristine with either cyclophosphamide, cisplatin or carboplatin) or OPEC/OJEC (etoposide, vincristine and cyclophosphamide with alternating cisplatin [OPEC] or carboplatin [OJEC]) induction chemotherapy in 2 Children's Cancer & Leukaemia Group (CCLG) pediatric oncology centers. The percentage of postchemotherapy necrosis was assessed and compared with MYCN amplification status and overall survival. The median percentage of postchemotherapy tumor necrosis was 60%. MYCN status was available for 28 cases, of which 12 were amplified (43%). Survival in cases with ≥ 60% necrosis or ≥ 90% necrosis was not better than those with less necrosis, nor was percentage necrosis associated with survival using Cox regression. However, MYCN-amplified tumors showed a higher percentage of necrosis than non-MYCN-amplified tumors, 71.3% versus 37.2% (P = .006). This effect was not related to prechemotherapy necrosis and did not confer improved overall survival. Postchemotherapy tumor necrosis is higher in patients with MYCN amplification. In this study, postchemotherapy necrosis did not correlate with overall survival and should not lead to modification of postoperative treatment. However, these findings need to be confirmed in a larger prospective study of children with high-risk neuroblastoma.

Transplantation for congenital heart disease is associated with an increased risk of Epstein-Barr virus-related post-transplant lymphoproliferative disorder in children.

BACKGROUND: Children undergoing heart transplant are at higher risk of developing post-transplant lymphoproliferative disorder (PTLD) than other solid organ recipients. The factors driving that risk are unclear. This study investigated risk factors for PTLD in children transplanted at 1 of 2 United Kingdom pediatric cardiac transplantation centers. METHODS: All children (<18 years, n = 200) transplanted at our institution over a 16-year period were analyzed. Freedom from PTLD was assessed using the Kaplan-Meier method and Cox proportional regression. RESULTS: PTLD occurred in 17 of 71 children transplanted for congenital heart disease (CHD) and 18 of 129 transplanted for acquired cardiomyopathy (ACM). The cumulative incidence of all PTLD was 21.1% at 5 years after transplant. Median time from transplant to PTLD was 2.9 years (interquartile range: 0.9-4.6). Negative Epstein-Barr virus (EBV) serostatus pre-transplant (adjusted hazard ratio [HR]: 2.7, 95% CI: 1.3-5.6, p = 0.01) and underlying CHD (adjusted HR: 3.2, 95% CI: 1.4-7.4, p = 0.007) were independently associated with higher risk of PTLD. Age at thymectomy was significantly different between children with CHD and ACM (0.4 vs 5.5 years, p < 0.01). Median CD4+ and CD8+ T lymphocyte counts at 2 years after transplant were significantly lower in children transplanted for CHD vs ACM (CD4+: 391/µl vs 644/µl, p = 0.01; CD8+: 382/µl vs 500/µl, p = 0.01). At 5 years after transplant, those differences persisted among patients who developed PTLD (CD4+, 430/µl vs 963/µl, p < 0.01 and CD8+, 367/µl vs 765/µl, p < 0.01). CONCLUSION: Underlying CHD is an independent risk factor for PTLD and is associated with a younger age at thymectomy. A persistent association with altered T lymphocyte subsets may contribute to the impaired response to primary EBV infection and increase the risk of PTLD.

Author Correction: High-dose chemotherapy and autologous stem cell transplantation in enteropathy-associated and other aggressive T-cell lymphomas: a UK NCRI/Cancer Research UK Phase II Study.

In the original version of this article, the mention of 'ifosfamide 1500 mg/m2 days 1-3' should, in fact, read 'ifosfamide 1500 mg/m2 bd days 1-3'. This has now been updated in the original version of the article.

Invasive aspergillosis of the small bowel in an infant with acute myeloid leukemia and intestinal obstruction.

Acute myeloid leukemia was diagnosed in an infant with fever and pancytopenia. Intestinal obstruction was present at diagnosis and laparotomy performed after failure of conservative management demonstrated leukemic infiltration of the resected terminal ileum. Fever and intestinal obstruction persisted, necessitating a second ileal resection, which revealed invasive aspergillosis. Subsequent retrospective analysis identified occasional fungal hyphae in the initial resection specimen. With the combination of intensive chemotherapy and aggressive prolonged antifungal therapy the child survived. Invasive aspergillosis may unusually present at nonpulmonary sites at initial presentation of acute leukemia. Microbiological or histological diagnosis is needed to guide aggressive appropriate management.