Clinical impact and cost-consequence analysis of ePlex® blood culture identification panels for the rapid diagnosis of bloodstream infections: a single-center randomized controlled trial.

To assess clinical impact and perform cost-consequence analysis of the broadest multiplex PCR panels available for the rapid diagnosis of bloodstream infections (BSI). Single-center, randomized controlled trial conducted from June 2019 to February 2021 at a French University hospital with an institutional antimicrobial stewardship program. Primary endpoint was the percentage of patients with optimized antimicrobial treatment 12 h after transmission of positivity and Gram stain results from the first positive BC. This percentage was significantly higher in the multiplex PCR (mPCR) group (90/105 = 85.7% %, CI95% [77.5 ; 91.8] vs. 68/107 = 63.6%, CI95% [53.7 ; 72.6]; p < 10- 3) at interim analysis, resulting in the early termination of the study after the inclusion of 309 patients. For patients not optimized at baseline, the median time to obtain an optimized therapy was much shorter in the mPCR group than in the control group (6.9 h, IQR [2.9; 17.8] vs. 26.4 h, IQR [3.4; 47.5]; p = 0.001). Early optimization of antibiotic therapy resulted in a non-statistically significant decrease in mortality from 12.4 to 8.8% (p = 0.306), with a trend towards a shorter median length of stay (18 vs. 20 days; p = 0.064) and a non-significant reduction in the average cost per patient of €3,065 (p = 0.15). mPCR identified all the bacteria present in 88% of the samples. Despite its higher laboratory cost, the use of multiplex PCR for BSI diagnosis leads to early-optimised therapy, seems cost-effective and could reduce mortality and length of stay. Their impact could probably be improved if implemented 24/7.

Intramural gastric abscesses in a dog.

A 6-year-old, female neutered Labrador retriever was presented with a chronic history of vomiting and anorexia. Abdominal ultrasound identified two large cavitated structures with echogenic content in the gastric fundus and pyloric region. CT revealed the intraparietal nature of these structures, one in the greater curvature and another one extending from the lesser curvature to the pyloric antrum. Surgical exploration revealed two areas of thickened gastric wall with intramural purulent material. Debridement and partial resection of the abscess (deroofing) were performed via a routine gastrotomy approach. Histopathology of a gastric wall sample revealed neutrophilic inflammation with intralesional vegetal foreign body. The presence of intralesional foreign body with a positive bacterial culture and macroscopic absence of peritonitis may suggest an intramural migrating vegetal foreign body. Gastric wall abscess should be included in a differential diagnosis in dogs with a history of chronic vomiting and the presence of gastric wall cavitated structures. Surgical debridement through a routine gastrotomy opening alleviated the clinical signs related to the intramural gastric abscesses in this dog with no recurrence at 22 months.

Structural and functional studies of the metalloregulator Fur identify a promoter-binding mechanism and its role in Francisella tularensis virulence.

Francisella tularensis is a Gram-negative bacterium causing tularaemia. Classified as possible bioterrorism agent, it may be transmitted to humans via animal infection or inhalation leading to severe pneumonia. Its virulence is related to iron homeostasis involving siderophore biosynthesis directly controlled at the transcription level by the ferric uptake regulator Fur, as presented here together with the first crystal structure of the tetrameric F. tularensis Fur in the presence of its physiological cofactor, Fe2+. Through structural, biophysical, biochemical and modelling studies, we show that promoter sequences of F. tularensis containing Fur boxes enable this tetrameric protein to bind them by splitting it into two dimers. Furthermore, the critical role of F. tularensis Fur in virulence and pathogenesis is demonstrated with a fur-deleted mutant showing an attenuated virulence in macrophage-like cells and mice. Together, our study suggests that Fur is an attractive target of new antibiotics that attenuate the virulence of F. tularensis.

Are guidelines on the management of non-tuberculous mycobacteria lung infections respected and what are the consequences for patients? A French retrospective study from 2007 to 2014.

Diagnosis and treatment of lung infections caused by non-tuberculous mycobacteria (NTM) remain challenging. Adherence of the clinicians to the American Thoracic Society (ATS) and the Infectious Diseases Society of America (IDSA) 2007 guidelines is often incomplete. Between 2007 and 2014, in Grenoble Alpes University Hospital, France, 132 patients had NTM-positive cultures from lower respiratory tract (LRT) samples. We retrospectively collected diagnosis, treatment, and outcome data of patients, and evaluated the adherence of clinicians to ATS/IDSA guidelines and the consequences of patients' prognoses. Using the ATS/IDSA definitions, 31 out of 132 patients (23.5%) were considered infected, 57 out of 132 patients (43.2%) were considered colonised, 33 out of 132 (25%) were contaminated and 11 (8.4%) had missing data. Among the 31 NTM-infected patients, M. avium (23 out of 31, 74.2%) was most frequently involved. The main risk factor for NTM lung infection was underlying lung disease (30 out of 31, 96.8%). Treatment was not appropriate according to current guidelines in 58.1% of infected patients (18 out of 31). Mainly, the antibiotic treatment was installed based on radiological signs (p = 0.0006), sputum results and bronchoalveolar lavage results (p < 0.0001 and p = 0.003 respectively). Most antibiotic regimens included a macrolide (83.4%). Patients receiving appropriate treatment had the same cure rates as those receiving inappropriate treatment (p = 0.22) and similar relapse rates (p = 0.92). Current medical practices for the treatment of NTM lung infections in our institution are not consistent with the ATS/IDSA guidelines. This could potentially affect the prognosis of these patients and favour the emergence of macrolide resistance in NTM species.

Dorsal surgical stabilisation using tension bands for treatment of traumatic atlanto-occipital instability in a cat.

CASE REPORT: An atlanto-occipital instability secondary to a dog bite was diagnosed in a 4-year-old Persian cat. Dorsal stabilisation of the instability was made with two OrthoFiber prostheses (Securos), which were used as tension bands between the nuchal crests of the occipital bone and the spinous process of the axis. Total recovery was achieved 4 days after surgery. Normal alignment of the atlanto-occipital joint was observed on survey radiographs taken 6 weeks post-surgery. Although the right loop had failed, the alignment was still normal and no neurological after-effects could be identified. CONCLUSION: Dorsal divergent tension bands between the nuchal crests of the occipital bone and the spinous process of the axis can be used to stabilise traumatic atlanto-occipital instability.

Brucella suis biovar 2 infection in humans in France: emerging infection or better recognition?

Brucellosis is usually acquired by humans through contact with infected animals or the consumption of raw milk from infected ruminants. Brucella suis biovar 2 (BSB2) is mainly encountered in hares and wild boars (Sus scrofa), and is known to have very low pathogenicity to humans with only two case reports published in the literature. Human cases of brucellosis caused by BSB2 were identified through the national mandatory notification of brucellosis. The identification of the bacterium species and biovar were confirmed by the national reference laboratory. Epidemiological data were obtained during medical follow-up visits. Seven human cases were identified between 2004 and 2016, all confirmed by the isolation of BSB2 in clinical specimens. All patients had direct contact with wild boars while hunting or preparing wild boar meat for consumption. Five patients had chronic medical conditions possibly responsible for an increased risk of infection. Our findings suggest that BSB2 might be an emerging pathogen in hunters with massive exposure through the dressing of wild boar carcasses. Hunters, especially those with chronic medical conditions, should be informed about the risk of BSB2 infection and should receive information on protective measures.

Biochips for Direct Detection and Identification of Bacteria in Blood Culture-Like Conditions.

Bloodstream bacterial infections are life-threatening conditions necessitating prompt medical care. Rapid pathogen identification is essential for early setting of the best anti-infectious therapy. However, the bacterial load in blood samples from patients with bacteremia is too low and under the limit of detection of most methods for direct identification of bacteria. Therefore, a preliminary step enabling the bacterial multiplication is required. To do so, blood cultures still remain the gold standard before bacteremia diagnosis. Bacterial identification is then usually obtained within 24 to 48 hours -at least- after blood sampling. In the present work, the fast and direct identification of bacteria present in blood cultures is completed in less than 12 hours, during bacterial growth, using an antibody microarray coupled to a Surface Plasmon Resonance imager (SPRi). Less than one bacterium (Salmonella enterica serovar Enteritidis) per milliliter of blood sample is successfully detected and identified in blood volumes similar to blood tests collected in clinics (i.e. several milliliters). This proof of concept demonstrates the workability of our method for human samples, despite the highly complex intrinsic nature of unprocessed blood. Our label-free method then opens new perspectives for direct and faster bacterial identification in a larger range of clinical samples.

In vitro and in vivo evaluation of fluoroquinolone resistance associated with DNA gyrase mutations in Francisella tularensis, including in tularaemia patients with treatment failure.

Fluoroquinolones (FQs) are highly effective for treating tularaemia, a zoonosis caused by Francisella tularensis, but failures and relapses remain common in patients with treatment delay or immunocompromised status. FQ-resistant strains of F. tularensis harboring mutations in the quinolone-resistance determining region (QRDR) of gyrA and gyrB, the genes encoding subunits A and B of DNA gyrase, have been selected in vitro. Such mutants have never been isolated from humans as this microorganism is difficult to culture. In this study, the presence of FQ-resistant mutants of F. tularensis was assessed in tularaemia patients using combined culture- and PCR-based approaches. We analyzed 42 F. tularensis strains and 82 tissue samples collected from 104 tularaemia cases, including 32 (30.7%) with FQ treatment failure or relapse. Forty F. tularensis strains and 55 clinical samples were obtained before any FQ treatment, while 2 strains and 15 tissue samples were collected after treatment. FQ resistance was evaluated by the minimum inhibitory concentration (MIC) for the bacterial strains, and by newly developed PCR-based methods targeting the gyrA and gyrB QRDRs for both the bacterial strains and the clinical samples. None of the F. tularensis strains displayed an increased MIC compared with FQ-susceptible controls. Neither gyrA nor gyrB QRDR mutation was found in bacterial strains and tissue samples tested, including those from patients with FQ treatment failure or relapse. Further phenotypic and genetic resistance traits should be explored to explain the poor clinical response to FQ treatment in such tularaemia patients.

Human brucellosis in France in the 21st century: Results from national surveillance 2004-2013.

Brucellosis is a bacterial zoonotic disease mainly transmitted to humans by ruminants. In France, brucellosis has disappeared from ruminants herds. Human brucellosis surveillance is performed through mandatory notification and the national reference center. METHODS: We report the results of human brucellosis surveillance from 2004 to 2013 with regards to epidemiological, clinical and microbiological data. RESULTS: A total of 250 cases were notified, making an annual incidence of 0.3 cases per million inhabitants. Brucella melitensis biovar 3 was the most frequently identified bacterium (79% of isolated strains). In total, 213 (85%) cases had been contaminated abroad in endemic countries. In 2012, an episode of re-emergence of brucellosis in cattle occurred in Haute-Savoie, in the French Alps, and was responsible for 2 human cases. CONCLUSION: Brucellosis has become a disease of travelers in France. However, maintaining a stringent epidemiological surveillance is necessary to be able to early detect any local re-emergence in humans or animals. The multidisciplinary surveillance was implemented in France years ago and is a successful example of the One Health Concept.

[Usefulness of a rapid intrapartum real-time PCR assay in comparison with the group B Streptococcus culture screening at the end of pregnancy in pregnant women]. / Intérêt d'un test de PCR en temps réel en intrapartum en comparaison à la culture de fin de grossesse pour le dépistage du streptocoque du groupe B chez la femme enceinte.

OBJECTIVES: The objectives were to evaluate and compare the diagnostic accuracy of a rapid real-time PCR assay at the onset of labor with those of the current antenatal culture-based test at 34-38 weeks gestation for group B Streptococcus (GBS) screening. MATERIALS AND METHODS: A prospective study including all pregnant women admitted for delivery after a 34-week gestation period was conducted in October 2012 at the Grenoble University Hospital Centre. A first culture-based GBS screening test was performed between 34 and 38 weeks of gestation followed by a second screening test at the onset of labor, using a real-time PCR Assay and a culture-based method (gold standard) in order to calculate the diagnostic accuracy. RESULTS: One hundred an fifty-seven patients were enrolled. The sensitivity was 94.4% (95% CI, 72.7-99.9%) with intrapartum PCR assay and 50% (95% CI, 26-74%) with antepartum culture. Prevalence of GBS colonization was 7.6% with the antepartum culture method, 11.5% with intrapartum culture and 16.6% by using PCR-test. CONCLUSION: Intrapartum PCR shows a much higher sensitivity compared to the antepartum culture-based screening mainly due to variations in GBS colonization and could allow us to target patients requiring intrapartum antibiotic prophylaxis more effectively.

Survey of laboratory-acquired infections around the world in biosafety level 3 and 4 laboratories.

Laboratory-acquired infections due to a variety of bacteria, viruses, parasites, and fungi have been described over the last century, and laboratory workers are at risk of exposure to these infectious agents. However, reporting laboratory-associated infections has been largely voluntary, and there is no way to determine the real number of people involved or to know the precise risks for workers. In this study, an international survey based on volunteering was conducted in biosafety level 3 and 4 laboratories to determine the number of laboratory-acquired infections and the possible underlying causes of these contaminations. The analysis of the survey reveals that laboratory-acquired infections have been infrequent and even rare in recent years, and human errors represent a very high percentage of the cases. Today, most risks from biological hazards can be reduced through the use of appropriate procedures and techniques, containment devices and facilities, and the training of personnel.

Correlation between clinical data and antibiotic resistance in coagulase-negative Staphylococcus species isolated from 68 patients with acute post-cataract endophthalmitis.

Coagulase-negative staphylococci (CNS) cause the majority of post-cataract endophthalmitis, which can lead to anatomical and/or functional loss of the eye. This study reports the antibiotic susceptibilities of CNS isolates associated with acute post-cataract endophthalmitis cases and correlates antibiotic resistance with severity and outcome of infection in these patients. Clinical data (initial ocular examination, final prognosis, antibiotic treatment) and the antibiotic susceptibilities of the isolated CNS strains were obtained from 68 patients with post-surgical endophthalmitis recruited during a 7-year period by the FRench Institutional ENDophthalmitis Study (FRIENDS) group. The CNS strains displayed 100% susceptibility to vancomycin, 70% to fluoroquinolones, 83% to fosfomycin, 46% to imipenem and 18% to piperacillin. The most effective antibiotic combinations were fosfomycin plus a fluoroquinolone and imipenem plus a fluoroquinolone, which were considered adequate in 80% and 58% of patients, respectively. Methicillin resistance was significantly associated with older age (p 0.001), diabetes mellitus (p 0.004), absence of fundus visibility (p 0.06), and poor visual prognosis (p 0.03). Resistance to fluoroquinolones was significantly associated with absence of fundus visibility (p 0.05) and diabetes mellitus (p 0.02). This large prospective study demonstrates that methicillin resistance and, to a lesser extent, fluoroquinolone resistance in CNS strains causing postoperative endophthalmitis are both prevalent in France and associated with a poorer visual prognosis. These results emphasize the need for an effective surveillance of this antibiotic resistance and the development of new diagnostic tools for rapid detection for early optimization of antibiotic therapy in endophthalmitis patients.

[Vitamin D status in 6- to 10-year-old children: a French multicenter study in 326 children]. / Statut en vitamine D des enfants de 6 à 10ans : étude nationale multicentrique chez 326 enfants.

OBJECTIVE: To assess the vitamin D status of children aged 6-10years in the French general population for whom no guidelines have yet been defined due to insufficient data. METHOD: The study was conducted during two winters with very different sunshine levels: 5 March to 17 April 2012 and 8 January to 16 April 2013 in 20 then 22 centers. Three hundred children (60 children for each year of age) attending an ambulatory care unit or outpatient department for a reason unrelated to vitamin D status were included at the end of winter in 20 hospital centers (ten centers in the northern half of France above latitude 46-47°N/Lille: 50°N and ten centers in the southern half of France below latitude 46-47°N/Marseille: 43°N). Centralized 25 hydroxyvitamin D (25(OH)D), alkaline phosphatase (ALP), and parathormone (PTH) assays were performed on leftover blood samples. The currently accepted normal range for 25(OH)D was used to define the following categories: ≤25nmol/L: severe vitamin D deficiency, 25nmol/L100nmol/L: high vitamin D status. A standardized questionnaire was used to collect the child's characteristics, use of a vitamin D supplement, and milk and dairy product intake. The cumulative number of hours of sunshine over the 90days prior to inclusion in each center was obtained from the Météo-France weather bureau. RESULTS: 25(OH)D assays were performed in 326 children; more than 95% of children received milk and dairy products and 38% had received a vitamin D supplement since starting the school year: 3.1% of children in the overall population presented severe vitamin D deficiency, 34.4% presented vitamin D deficiency, 53.1% had a sufficient vitamin D status, and 9.5% had a 25(OH)D concentration >100nmol/L with no impact on serum calcium and urinary calcium. Children living in the north of France generally had lower 25(OH)D levels than children living in the south of France. In the non-supplemented population (n=188), 5.3% of children presented severe vitamin D deficiency, 45.2% presented vitamin D deficiency and 48.4% had sufficient 25(OH)D levels. The percentage of children with severe vitamin D deficiency or vitamin D deficiency was twofold higher during the winter with poor sunshine compared to the sunnier winter with a less marked north/south difference. No case of severe vitamin D deficiency was observed in the supplemented population (n=119); 10-15% of children presented vitamin D deficiency and 22.7% had a 25(OH)D concentration >100nmol/L, while remaining within the acceptable range. Two cases of hypervitaminosis without hypercalcemia were identified: one after an unknown loading dose with a calcium/creatinine ratio in the normal range (0.8); for the second one, no additional information could be obtained. Vitamin D supplementation considerably reduced the north/south difference and the Winter1/Winter2 difference. A child not receiving a vitamin D supplement had a ninefold higher risk of vitamin D deficiency at the end of winter than a child receiving a vitamin D supplement (OR=8.8; 95%CI, 4.6-16.8). CONCLUSION: At least one-third of children aged 6-10years presented deficient 25(OH)D levels. None of the children receiving a vitamin D supplement presented severe vitamin D deficiency, only a small number of children presented vitamin D deficiency (n=16 (13.4%)), and no signs of overload were observed, while one half of non-supplemented children (n=95 (50.5%)) presented at least vitamin D deficiency at the end of winter. These results support the need for vitamin D supplementation during winter in children aged 6-10years.

FRIENDS Group: clinical and microbiological characteristics of post-filtering surgery endophthalmitis.

PURPOSE: To study the clinical and microbiological characteristics as well as the prognostic factors for post-filtering surgery endophthalmitis. METHODS: Twenty-three eyes were included in the study in four tertiary centres between 2004 and 2010. The clinical and microbiological data were collected prospectively (minimum follow-up, 6 months). Microbiological diagnosis was based on conventional cultures and panbacterial PCR (16SrDNA amplification and sequencing). RESULTS: The onset of endophthalmitis was early (<6 weeks) in 22 % of the cases and delayed in 78 %. Elevated intraocular pressure and hypopyon were more frequent in delayed than in early presentations (p = 0.04). By combining the results of culture and panbacterial PCR, a bacterial species could be identified in 73.9 % of the cases, including 56.5 % of commensal species of the digestive tract such as Moraxella spp., oropharyngeal streptococci and Enterococcus faecalis. Good final visual acuity (VA ≥ 20/40) was correlated with initial VA greater than light perception (p = 0.05). Poor final VA (≤20/400) was correlated with a higher virulence of the infecting bacterial species (p = 0.006), and was noted in all patients with early-onset endophthalmitis. CONCLUSION: Acute early- or delayed-onset post-filtering surgery endophthalmitis is frequently caused by bacteria of the digestive tract (e.g., Streptococcus and Enterococcus spp.). The combination of conventional cultures and panbacterial PCR allowed us to identify the causative microorganism in three-quarters of the cases, i.e., 21 % more cases than through culture alone. Despite adequate antibiotic and surgical treatment, the anatomical and visual prognosis remains poor.

Typhoidal tularemia: 2 familial cases.

Eastern France was not known as a region endemic for tularemia until year 2006. We report on 2 cases of typhoidal tularemia in Eastern France, a 43-year-old hospitalized woman and her husband. Diagnosis was established after fever clearance on serodiagnosis criteria. The source of infection is unclear. As persons in the same family may likely be exposed to a common zoonotic source of infection, tularemia should be considered in the etiologies of familial fever epidemics.

Emergence of tularemia in France: paradigm of the Burgundy region.

We report three consecutive cases of tularemia occurring in Burgundy, France, a region previously considered not endemic for tularemia. The patients presented with varied and unspecific clinical manifestations. The epidemiological circumstances, especially the mode of contamination, were not particularly suggestive of tularemia. Serological diagnosis was delayed in two cases because of the lack of significant antibody titers at the time of admission. In contrast, a diagnosis could readily be obtained in all three cases by detection of Francisella tularensis DNA from clinical samples using PCR-based methods. These cases highlight the increased incidence and geographical spread of tularemia in France, and the usefulness of real-time PCR technology for the early diagnostic confirmation of tularemia.

EHT0202 in Alzheimer's disease: a 3-month, randomized, placebo-controlled, double-blind study.

BACKGROUND: EHT0202 (etazolate hydrochloride) is a new compound exhibiting both potential disease-modifying and symptomatic treatment properties in Alzheimer's Disease increasing alpha-secretase activity and sAPP alpha secretion, as well as acting as a GABA-A receptor modulator and as a PDE-4 inhibitor. METHODS: This pilot, randomized, double-blind, placebo-controlled, parallel group, multicentre, Phase IIA study was conducted in 159 randomized patients suffering from mild to moderate Alzheimer's Disease. EHT0202 (40 or 80 mg bid) or placebo was administered as adjunctive therapy to one acetylcholinesterase inhibitor over a 3-month period. This study was designed to assess the clinical safety and tolerability of EHT0202 as a primary objective, with secondary endpoints (cognitive function, daily living activities, behaviour, caregiver burden and global functioning) included to explore clinical efficacy of EHT0202 versus placebo. RESULTS: EHT0202 was shown to be safe and generally well tolerated. Dose-dependent numbers of early withdrawal and central nervous system related adverse events were observed. As expected, since the study was not powered and not designed to show drug efficacy, and except for ratings on the ADCS-ADL scale, no significant differences were seen between treatment groups. CONCLUSIONS: These first encouraging safety results do support further development of EHT0202 in order to assess its clinical efficacy and to confirm its tolerability in a larger cohort of Alzheimer patients and for a longer period.

Targeted delivery of anti-cancer growth inhibitory peptides derived from human alpha-fetoprotein: review of an International Multi-Center Collaborative Study.

The alpha-fetoprotein derived growth inhibitory peptide (GIP) is a 34-amino acid peptide composed of three biologically active subfragments. GIP-34 and its three constituent segments have been synthesized, purified, and studied for biological activity. The GIP-34 and GIP-8 have been characterized as anticancer therapeutic peptides. An multicenter study was initiated to elucidate the means by which these peptide drugs could be targeted to tumor cells. The study first established which cancer types were specifically targeted by the GIP peptides in both in vitro and in vivo investigations. It was next demonstrated that radiolabeled peptide ((125)I GIP-34) is specifically localized to rodent breast tumors at 24 h post-injection. The radionuclide studies also provided evidence for a proposed cell surface receptor; this was confirmed in a further study using fluorescent-labeled GIP-nanobeads which localized at the plasma membrane of MCF-7 breast cancer cells. Finally, it was readily demonstrated that GIP conjugated to either fluorescein or doxorubicin (DOX) underwent tumor cell uptake; subsequently, DOX-GIP conjugates induced cytotoxic cell destruction indicating the utility of GIP segments as cancer therapeutic agents. Following a discussion of the preceding results, a candidate cell surface receptor family was proposed which correlated with previous published reports for a putative AFP/GIP receptor.

[Unexpected increase of human and animal tularemia cases during winter 2007/2008 in France: Emergence or short-lasting episode?]. / Excès de cas humains et animaux de tularémie en France au cours de l'hiver 2007-2008 : émergence ou phénomène isolé ?

CONTEXT: Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008. METHODS: Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results. RESULTS: In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent. CONCLUSION: An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.

Chromosomal breakpoints characterization of two supernumerary ring chromosomes 20.

The occurrence of an additional ring chromosome 20 is a rare chromosome abnormality, and no common phenotype has been yet described. We report on two new patients presenting with a supernumerary ring chromosome 20 both prenatally diagnosed. The first presented with intrauterine growth retardation and some craniofacial dysmorphism, and the second case had a normal phenotype except for obesity. Conventional cytogenetic studies showed for each patient a small supernumerary marker chromosome (SMC). Using fluorescence in situ hybridization, these SMCs corresponded to ring chromosomes 20 including a part of short and long arms of chromosome 20. Detailed molecular cytogenetic characterization showed different breakpoints (20p11.23 and 20q11.23 for Patient 1 and 20p11.21 and 20q11.21 for Patient 2) and sizes of the two ring chromosomes 20 (13.6 Mb for case 1 and 4.8 Mb for case 2). Review of the 13 case reports of an extra r(20) ascertained postnatally (8 cases) and prenatally (5 cases) showed varying degrees of phenotypic abnormalities. We document a detailed molecular cytogenetic chromosomal breakpoints characterization of two cases of supernumerary ring chromosomes 20. These results emphasize the need to characterize precisely chromosomal breakpoints of supernumerary ring chromosomes 20 in order to establish genotype-phenotype correlation. This report may be helpful for prediction of natural history and outcome, particularly in prenatal diagnosis.