Truncating variants in the penultimate exon of TGFBR1 escaping nonsense-mediated mRNA decay cause Loeys-Dietz syndrome

Pathogenic variants in TGFBR1 are a common cause of Loeys-Dietz syndrome (LDS) characterized by life-threatening aortic and arterial disease. Generally, these are missense changes in highly conserved amino acids in the serine-threonine kinase domain. Conversely, nonsense, frameshift, or specific missense changes in the ligand-binding extracellular domain cause multiple self-healing squamous epithelioma (MSSE) lacking the cardiovascular phenotype. Here, we report on two novel variants in the penultimate exon 8 of TGFBR1 were identified in 3 patients from two unrelated LDS families: both were predicted to cause frameshift and premature stop codons (Gln448Profs*15 and Cys446Asnfs*4) resulting in truncated TGFBR1 proteins lacking the last 43 and 56 amino acid residues, respectively. These were classified as variants of uncertain significance based on current criteria. Transcript expression analyses revealed both mutant alleles escaped nonsense-mediated mRNA decay. Functional characterization in patient's dermal fibroblasts showed paradoxically enhanced TGFβ signaling, as observed for pathogenic missense TGFBR1 changes causative of LDS. In summary, we expanded the allelic repertoire of LDS-associated TGFBR1 variants to include truncating variants escaping nonsense-mediated mRNA decay. Our data highlight the importance of functional studies in variants interpretation for correct clinical diagnosis.

A meta-analysis on the changes of BMI during an inpatient treatment with different follow-up lengths (short and long term) compared with the outpatient phase in obese patients

BACKGROUND

The management of obesity should be multidimensional based on the choice of the treatment and the intensity of the therapeutic-rehabilitative intervention. This meta-analysis aims to compare the changes on body weight and body mass index (BMI) during an inpatient treatment (hospitalized weight loss programs with different durations in terms of weeks) compared with the outpatient phase.

METHODS

The data obtained from the studies on inpatients have been layered into two categories: short term (studies with follow-up of max 6 months) and long term (studies with follow-up up to 24 months). Furthermore, this study evaluates which of the two approaches show the best impact on weight loss and BMI during 2 follow-ups at 6 to 24 months.

RESULTS

The analysis, which included seven studies (977 patients), revealed that the subjects underwent a short hospitalization had greater benefit, compared to those who were followed for a long time. The meta-analyzed mean differences for random effect (MD) showed a statistically significant decrease on BMI of -1.42 kg/m² (95% CI: -2.48 to -0.35; P = 0.009) and on body weight -6.94 (95% CI: -10.71 to -3.17; P = 0.0003) for subjects who carry out a short hospitalization compared to outpatients. No reduction of body weight (p = 0.07) and BMI (p = 0.9) for subjects who undergo a long hospitalization compared to an outpatient.

CONCLUSIONS

A short-term inpatients multidisciplinary weight loss program could be the best choice for the management of obesity and its related comorbidities; on the contrary, if the follow-up is of long duration, the significance is not confirmed. The hospitalization at the beginning of any obesity treatment is significantly better than only outpatients treatment.

Homozygous TNNI3 Mutations and Severe Early Onset Dilated Cardiomyopathy: Patient Report and Review of the Literature

The TNNI3 gene encodes for the cardiac isoform of troponin I, a pivotal component of the sarcomeric structure of the myocardium. While heterozygous TNNI3 missense mutations have long been associated with autosomal dominant hypertrophic and restrictive cardiomyopathies, the role of TNNI3 null mutations has been more debated due to the paucity and weak characterization of reported cases and the low penetrance of heterozygous genotypes. In recent years, however, an increasing amount of evidence has validated the hypothesis that biallelic TNNI3 null mutations cause a severe form of neonatal dilated cardiomyopathy. Here, we expand the case series reporting two unrelated patients afflicted with early onset dilated cardiomyopathy, due to homozygosity for the p.Arg98* TNNI3 variant, which had thus far been documented only in heterozygous patients and apparently healthy carriers, and the recurrent p.Arg69Alafs*8 variant, respectively. A review of previously reported biallelic TNNI3 loss-of-function variants and their associated cardiac phenotypes was also performed.

From clinical to molecular diagnosis: relevance of diagnostic strategy in two cases of branchio-oto-renal syndrome - case report

Background

Branchio-oto-renal syndrome (BOR) is an autosomal dominant disorder characterized by deafness, branchiogenic malformations and renal abnormalities. Pathogenic variants in EYA1, SIX1 and SIX5 genes cause almost half of cases; copy number variants (CNV) and complex genomic rearrangements have been revealed in about 20% of patients, but they are not routinely and commonly included in the diagnostic work-up.

Case presentation

We report two unrelated patients with BOR syndrome clinical features, negative sequencing for BOR genes and the identification of a 2.65 Mb 8q13.2–13.3 microdeletion.

Conclusions

We highlight the value of CNV analyses in high level of suspicion for BOR syndrome but negative sequencing for BOR genes and we propose an innovative diagnostic flow-chart to increase current detection rate. Our report confirms a mechanism of non-allelic homologous recombination as causing this recurrent 8q13.2–13.3 microdeletion. Moreover, considering the role of PRDM14 and NCOA2 genes, both involved in regulation of fertility and deleted in our patients, we suggest the necessity of a longer follow-up to monitor fertility issues or additional clinical findings.

Associations of urinary and dietary cadmium with urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine and blood biochemical parameters

Cadmium is a heavy metal with established adverse effects on human health, namely on bone, liver and kidney function and the cardiovascular system. We assessed cadmium exposure and its correlation with biomarkers of toxicity. We recruited 137 non-smoking blood donors without a history of chronic disease or cancer who resided in the Northern Italy province of Reggio Emilia (mean age 47 years, range 30-60 years) in the 2017-2019 period. We used a semi-quantitative food frequency questionnaire to estimate dietary cadmium intake and urine samples to assess concentrations of urinary cadmium and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG). Median urinary cadmium and 8-oxodG concentrations were 0.21 μg/L (interquartile range (IQR): 0.11-0.34 μg/L) and 3.21 μg/g creatinine (IQR: 2.21-4.80 μg/g creatinine), respectively, while median dietary cadmium intake was 6.16 μg/day (IQR: 5.22-7.93 μg/day). We used multivariable linear and spline regression models to estimate mean differences exposure concentrations. Dietary and urinary cadmium were positively correlated, and both were positively and linearly correlated with 8-oxodG. We found a positive association of urinary cadmium with blood alanine aminotransferase (ALT), total cholesterol, low-density lipoprotein (LDL)-cholesterol and thyroid-stimulating hormone (TSH) concentrations. We also observed a positive association with triglycerides, in both linear (beta regression coefficient = 77.03, 95% confidence interval 32.27-121.78) and non-linear spline regression analyses. Despite the positive correlation between dietary and urinary cadmium estimates, dietary cadmium intake showed inconsistent results with the study endpoints and generally weaker associations, suggesting a decreased capacity to reflect actual cadmium exposure. Overall, these findings suggest that even low levels of cadmium exposure may adversely alter hematological and biochemical variables and induce oxidative stress.

The Potential Roles of Very Low Calorie, Very Low Calorie Ketogenic Diets and Very Low Carbohydrate Diets on the Gut Microbiota Composition

Several studies have described a strong correlation between diet, weight loss, and gut microbiota composition. The aim of this review was to evaluate the potential effects of energy-restricted diets, namely very low calorie diets (VLCDs), very low calorie ketogenic diets (VLCKDs), and very low carbohydrate diets (VLCarbDs), on the composition of the gut microbiota in humans. We performed a literature search using the following terms (with their abbreviations or acronyms): "very low calorie diet", "very low calorie ketogenic diet", "very low carbohydrate diet", and "gut microbiota". Our search strategy retrieved nine eligible studies. Overall, VLCDs and VLCarbDs affected the Bacteroidetes to Firmicutes ratio in obese patients, leading to a reduction in short-chain fatty acid production by fecal microbiota associated with Clostridial cluster XIVa. This reduction particularly affected Roseburia and Eubacterium rectale, the two most abundant butyrate-producing bacteria in human feces. VLCKDs preserved the core fecal microbiome, but altered the composition of fecal microbial populations in relation to the plasma metabolome and fecal bile acid composition. In particular, VLCKD-induced weight loss resulted in a reduction in E. rectale and Roseburia, an increase in Christensenellaceae and Akkermansia while not all studies show a decrease in Faecalibacterium prausnitzii. Although very few studies have analyzed the effects of VLCarbDs and VLCDs on gut microbiota, significant diet-induced changes in fecal microbiota composition have been observed. Further studies are needed.

Corrigendum: The Potential Roles of Very Low Calorie, Very Low Calorie Ketogenic Diets and Very Low Carbohydrate Diets on the Gut Microbiota Composition

[This corrects the article DOI: 10.3389/fendo.2021.662591.].

Auditory Outcome after Cochlear Implantation in Children with DFNB7/11 Caused by Pathogenic Variants in TMC1 Gene

INTRODUCTION

Non-syndromic hereditary hearing loss is characterized by extreme genetic heterogeneity. So far, more than 100 pathogenic or likely pathogenic variants in TMC1 gene have been reported in patients with autosomal recessive hearing loss (HL) DFNB7/11. The prevailing auditory phenotype of individuals with DFNB7/11 is congenital, profound, bilateral HL, but the functional outcome after cochlear implantation (CI) described in the literature is variable. The objective of this work is to evaluate the auditory outcome after CI in pediatric patients with DFNB7/11, born to non-consanguineous parents.

METHODS

A retrospective analysis of genetic and audiological data of DFNB7/11 patients followed up in a single Italian otolaryngology clinic was performed. Cases with biallelic pathogenic variants in TMC1 were selected from the cohort of children with non-syndromic hearing loss who had undergone CI and had been molecularly characterized by multigene panel testing. All patients underwent extensive audiological assessment, and the auditory outcome after CI was evaluated.

RESULTS

DFNB7/11 was diagnosed in a total of 3 patients from 2 non-consanguineous families; a novel disease-causing variant in TMC1 was detected [c.962G>A p.(Trp321*)]. All the affected children showed the typical DFNB7/11 phenotype characterized by prelingual, severe-to-profound HL. The patients showed an excellent functional outcome after CI; speech perception, nonverbal cognition, and speech performance were comparable to those of patients with DFNB1 deafness.

DISCUSSION/CONCLUSION

Our results do not support the variable auditory outcome reported in the literature, which may be affected by several social and environmental factors and by the genetic background.

Ideal food pyramid for patients with rheumatoid arthritis: A narrative review

Emerging literature suggests that diet plays an important modulatory role in rheumatoid arthritis (RA) because diet is an environmental factor that affects inflammation, antigen presentation, antioxidant defense mechanisms and gut microbiota. Patients with RA frequently ask their doctors about which diets to follow, and even in the absence of advice from their physicians, many patients are undertaking various dietary interventions. Given this background, the aim of this review is to evaluate the evidence to date regarding the ideal dietary approach for management of RA in order to reduce the counteracting inflammation, and to construct a food pyramid for patients with RA. The pyramid shows that carbohydrates should be consumed every day (3 portions of whole grains, preferably gluten free), together with fruits and vegetables (5 portions; among which fruit, berries and citrus fruit are to be preferred, and among the vegetables, green leafy ones.), light yogurt (125 ml), skim milk (200 ml), 1 glass (125 ml) of wine and extra virgin olive oil; weekly, fish (3 portions), white meat (3 portions), legumes (2 portions) eggs (2 portions), seasoned cheeses (2 portions), and red or processed meats (once a week). At the top of the pyramid, there are two pennants: one green means that subjects with RA need some personalized supplementation (vitamin D and omega 3) and one red means that there are some foods that are banned (salt and sugar). The food pyramid allows patients to easily figure out what to eat.

Testing single/combined clinical categories on 5110 Italian patients with developmental phenotypes to improve array-based detection rate

Background

Chromosomal microarray analysis (CMA) is nowadays widely used in the diagnostic path of patients with clinical phenotypes. However, there is no ascertained evidence to date on how to assemble single/combined clinical categories of developmental phenotypic findings to improve the array‐based detection rate.

Methods

The Italian Society of Human Genetics coordinated a retrospective study which included CMA results of 5,110 Italian patients referred to 17 genetics laboratories for variable combined clinical phenotypes.

Results

Non‐polymorphic copy number variants (CNVs) were identified in 1512 patients (30%) and 615 (32%) present in 552 patients (11%) were classified as pathogenic. CNVs were analysed according to type, size, inheritance pattern, distribution among chromosomes, and association to known syndromes. In addition, the evaluation of the detection rate of clinical subgroups of patients allowed to associate dysmorphisms and/or congenital malformations combined with any other single clinical sign to an increased detection rate, whereas non‐syndromic neurodevelopmental signs and non‐syndromic congenital malformations to a decreased detection rate.

Conclusions

Our retrospective study resulted in confirming the high detection rate of CMA and indicated new clinical markers useful to optimize their inclusion in the diagnostic and rehabilitative path of patients with developmental phenotypes.

Forkhead box G1 gene haploinsufficiency: an emerging cause of dyskinetic encephalopathy of infancy

BACKGROUND

14q12 deletions, including the Forkhead Box G1 (FOXG1) gene and point mutations of this gene, are associated with a complex encephalopathy described as a congenital variant of Rett syndrome. A mixture of jerks, athetosis, chorea, and dystonia is observed early in life in many patients. The aim of this article is to report on the spectrum of movement disorders associated with FOXG1 haploinsufficiency, as described in the literature.

PATIENTS AND METHODS

We provide a review of the cases reported in the literature, adding two new patients. We searched for a comprehensive set of clinical features, including age at onset and semiology of the movement disorder, occurrence and type of stereotypies, and neurological outcome.

RESULTS

A total of 51 cases were included in our study. Nonepileptic abnormal movements occurred in 33 cases, often variably combined and presenting during the first year of life.

CONCLUSION

The neurological phenotype of FOXG1 haploinsufficiency shows the features of a dyskinetic encephalopathy of infancy.

A Hunter Patient with a Severe Phenotype Reveals Two Large Deletions and Two Duplications Extending 1.2 Mb Distally to IDS Locus

Mucopolysaccharidosis type II (Hunter syndrome, MPS II) is an X-linked lysosomal storage disorder caused by the deficit of iduronate 2-sulfatase (IDS), an enzyme involved in the glycosaminoglycans (GAGs) degradation. We here report the case of a 9-year-old boy who was diagnosed with an extremely severe form of MPS II at 10 months of age. Sequencing of the IDS gene revealed the deletion of exons 1-7, extending distally and removing the entire pseudogene IDSP1. The difficulty to define the boundaries of the deletion and the particular severity of the patient phenotype suggested to verify the presence of pathological copy number variations (CNVs) in the genome, by the array CGH (aCGH) technology. The examination revealed the presence of two deletions alternate with two duplications, overall affecting a region of about 1.2 Mb distally to IDS gene. This is the first complex rearrangement involving IDS and extending to a large region located distally to it described in a severe Hunter patient, as evidenced by the CNVs databases interrogated. The analysis of the genes involved in the rearrangement and of the disorders correlated with them did not help to clarify the phenotype observed in our patient, except for the deletion of the IDS gene, which explains per se the Hunter phenotype. However, this cannot exclude a potential "contiguous gene syndrome" as well as the future rising of additional pathological symptoms associated with the other extra genes involved in the identified rearrangement.

De novo trisomy 20p characterized by array comparative genomic hybridization: report of a novel case and review of the literature

We report on a boy with speech delay, mental retardation, motor clumsiness, hyperactivity, dysmorphic facial features, brachytelephalangy and short stature. Electrocardiogram, echocardiography, renal ultrasound, electroencephalogram, fundoscopic exam and auditory brainstem responses were all normal. Brain magnetic resonance imaging showed a left temporal arachnoid cyst and a small pineal gland cyst. High resolution karyotype and FISH analysis detected a de novo duplication of the short arm of chromosome 20. A molecular characterization of the chromosomal anomaly was performed by array-CGH, confirming a 17.98 Mb duplication of the short arm of chromosome 20 associated with a small duplication on chromosome 3p, that was shown to be maternally inherited. This is one of the few cases of de novo trisomy 20p with extensive workup, characterization at molecular level and close follow-up from the neonatal period to age 30 months. We also compared the phenotype of our patient with that previously reported in literature, therefore contributing to better define the trisomy 20p syndrome and helping pediatricians and geneticists to better counsel families about the developmental prognosis of these children.

Association study of AMH and AMHRII polymorphisms with unexplained infertility

OBJECTIVE

To investigate the association of AMH and AMHRII polymorphisms with reproductive abilities in a sample of women with idiopathic infertility.

DESIGN

Case-control study.

SETTING

University Department of Obstetrics and Gynecology, and University Unit of Clinical Genetics.

PATIENT(S)

76 women with idiopathic sterility and 100 fertile women as controls.

INTERVENTION(S)

Genotyping was performed by high-resolution melt analysis.

MAIN OUTCOME MEASURE(S)

Genotype distribution and allele frequency of AMH and AMHRII polymorphisms. Reconstruction of haplotype alleles to evaluate the linkage disequilibrium between single nucleotide polymorphisms.

RESULT(S)

Allele frequencies of -482 A>G, IVS 5-6 C>T, IVS 10+77 A>G, 146T>G polymorphisms are statistically significantly different in infertile patients compared with controls.

CONCLUSION(S)

Genetic variants of AMH and AMHRII genes seem to be associated with infertility, suggesting a role in the pathophysiology of normo-estrogenic and normo-ovulatory infertility. A clearer understanding of their function in ovarian physiology may help clinicians to find a role for antimüllerian hormone measurement in the field of reproductive medicine.

Epidemiology of osteoarthritis: prevalence, risk factors and functional impact

Osteoarthritis (OA), the most common form of arthritis, is a major contributor to functional impairment and reduced independence in older adults. OA of the hip and knee are two of the most important causes of pain and physical disability in community-dwelling adults. Symptomatic hand OA is a common disease among the elderly, and impairs hand function, this impairment being largely mediated by pain. Like other chronic diseases, the etiology of OA is multifactorial, and several local and systemic risk factors have been identified. Differences in the prevalence of OA may be attributable to both genetic and life-style factors. Disease definition may be based upon clinical or radiographic criteria, although case definition should rely on radiographic features for epidemiological studies. This review focuses on the functional impact of the disease, describes geographic differences in prevalence rates, discusses disease definition criteria, and summarizes the most common risk factors, including age, associated with the risk of OA.

Vascular changes in psoriatic knee joint synovitis

OBJECTIVE

To evaluate the diagnostic utility of standard arthroscopy supported by a computerized image analysis system; and to examine and quantify the macroscopic appearance of blood vessels in selected anatomical areas, comparing 2 groups of patients with PsA and RA with refractory knee joint synovitis (KJS) for vascular marking (VM) features and VM scores, as well as for the relationship between respective VM scores and local and systemic KJS disease activity indices.

METHODS

Standard arthroscopy was carried out on 39 knees (20 PsA, 19 RA). Videorecordings of the examination were reanalyzed using a computer image analysis system and software. The appearance of vascular markings was assessed and separately scored for the areas of surface synovium (capsular, CVM), villous proliferation (villous, VVM), and synovium adherent to cartilage (pannus, PVM). Indices of systemic (erythrocyte sedimentation rate, ESR) and local KJS disease activity (clinical index) were obtained before arthroscopy. The morphology and scores of the distinct VM were compared between PsA and RA groups, as was the relationship between respective VM scores and ESR and KJS clinical indices.

RESULTS

Distinctive VM features were observed for PsA and RA KJS in each separate synovial architecture examined. VVM and CVM scores were significantly correlated with each other in PsA knees, and were significantly higher in PsA compared with RA. In both diseases, VVM and CVM scores were not related to KJS duration or activity or to ESR values, but in RA they were directly correlated with KJS activity. Moreover, the VVM capillary feature "meandering with tight convolutions," considered unique to psoriatic skin, was observed in the synovium of 13 PsA (65%) and one RA KJS (5.5%). The mean KJS duration of the PsA group with typical VVM was significantly lower than the group without VVM (2.6 +/- 1.77 vs 9.4 +/- 8.28 yrs).

CONCLUSION

Our macroscopic observations of distinct changes in VM expression in selected anatomical areas of PsA and RA KJS suggest possible pathogenetic differences between the 2 diseases. The typical morphology and higher intensity of villous vascularization, in both early and chronic disease, and the different clinical relevance of VVM scores in PsA compared with RA KJS support the potential use of vascular markings as reliable outcome measures of the PsA process in KJS.

Arthroscopic synovectomy in rheumatoid and psoriatic knee joint synovitis: long-term outcome

A long-term prospective study was performed to evaluate the safety and long-term outcome of surgical arthroscopy (AS) for persistent rheumatoid (RA) and psoriatic (PsA) knee joint synovitis (KJS). Local signs of joint inflammation (tenderness, swelling, "ballottement') and range of motion (ROM) were scored and the sum, taken as a global outcome measure, was recorded in 17 RA and 18 PsA knees, both before and at follow-up periods of 2, 6, 12, 24 and 36 months after surgical AS (knee joint synovectomy; meniscal curettage, cartilage shaving or chondrectomy, according to the degree of cartilage damage). A survival analysis (Kaplan-Meier) of the long-term outcome of surgical AS treatment and of the predictive value of clinical parameters of knee joint involvement was also performed. No intra- or post-operative morbidity, pain worsening or loss of joint motion was observed and all patients were discharged within 48 h. Comparison of the parameters of knee joint evaluation showed a significant reduction of the signs of joint inflammation and a significant increase in the ROM in all follow-up periods. At 36 months, the survival curves showed a 61.2% cumulative probability of clinical remission and 72.8% of definite improvement. No significant differences in the prognostic importance of RA, compared to PsA diagnosis, were observed, although higher percentages of PsA compared to RA knees (86.3% and 45.7% respectively) reached the end point of clinical remission at 36 months. KJS duration, radiographic severity and cartilage damage were not predictors of poor long-term outcome of AS synovectomy. Surgical AS treatment for PsA knees with more advanced cartilage damage gave a better long-term outcome. A total of 50.7% of operated knees reached the end point of a KJS relapse at 36 months, the majority (82%) within the initial 18 months of follow-up. Our study indicates that AS synovectomy is a safe procedure requiring short hospitalization which, in combination with second-line medical treatment, can reduce local inflammation in RA and PsA KJS, and preserve knee joint ROM for up to 3 yr.

Long-term sonographic follow-up of rheumatoid and psoriatic proliferative knee joint synovitis

The potential role of sonography in evaluating the response to therapy of persistent knee joint synovitis (KJS) was assessed in a longitudinal study in pre-and post-arthroscopic (AS) synovectomy in rheumatoid and psoriatic patients. At entry to the study ultrasound (US) detection of synovial proliferation was compared with arthroscopic visualization as the 'gold standard' reference. US joint effusion and synovial thickness measures and predominant patterns of synovial proliferation were recorded by comparing clinical and US indices before and at 2, 6 and 12 months after AS synovectomy, or after KJS relapse up to 24 months. A 12 month survival analysis of clinical and US outcomes of arthroscopic synovectomy was also performed. US detection of morphology and degree of synovial proliferation was correlated with AS macroscopic evaluation. After AS synovectomy, the clinical index and both US joint effusion and synovial thickness were significantly reduced, whereas US patterns of synovial proliferation did not show significant changes. US and clinical indices were significantly correlated in all follow-up measurements and US joint effusion was significantly increased in the relapsed compared with the non-relapsed KJS group. The probability at 12 months of reaching maximum improvement in US joint effusion and synovial thickness outcomes was 99 and 58%, respectively; that for clinical remission of KJS was 72%. Ultrasound evaluation has proven reliable and accurate by the arthroscopic gold standard in detecting changes of rheumatoid arthritis and psoriatic arthritis knee joint synovitis. The correlation of US with clinical findings in pre-and post synovectomy patients suggests that sonography can be used as an objective method in monitoring the response to therapy of inflammatory knee joint disease.

Prospective sonographic and arthroscopic evaluation of proliferative knee joint synovitis

The objective of this study was to verify the accuracy of ultrasonography in assessing the topography, morphology, and extent of synovial proliferation in rheumatoid and psoriatic knee joint synovitis. Findings were compared to those obtained using prospective arthroscopy as the gold standard; in addition, topographically defined sonographic findings before and after arthroscopic synovectomy were compared. Sonographic examination was performed in 12 patients with rheumatoid arthritis (13 knees) and 13 patients with psoriatic arthritis (14 knees) who had synovitis of the knee using an electronic linear transducer (7.5 MHz) or a mechanical sector transducer (10 MHz). This examination was followed within 1 week by arthroscopy, to compare the topography (intra-articular localization) and the morphology (sonographic patterns) of synovial proliferation. In 15 knees undergoing arthroscopic synovectomy, preoperative sonographic measurement of synovial thickness in the suprapatellar, medial parapatellar, and lateral parapatellar recesses was compared with arthroscopic visualization of synovial proliferation; 13 knees were reevaluated 2 months after arthroscopic synovectomy by sonography at the same sites. Three distinct sonographic patterns of synovial proliferation were confirmed by arthroscopic examination: a villonodular aspect in 12 knees; uniform thickening in eight knees, and overlapping layers in seven knees. About 50% of the knees showed more than one sonographic pattern, with no differences in pattern distribution between rheumatoid arthritis and psoriatic arthritis patients. A significant correlation was found between sonographic and arthroscopic evaluations of synovial thickness in the suprapatellar (P < 0.02) and medial parapateoffr recesses (P < 0.02), the sites of maximal synovial proliferation in our patients.(ABSTRACT TRUNCATED AT 250 WORDS)