Challenge and difficulty of diagnosing hemoglobinopathies in newborns: about a case / Enjeu et difficulté du diagnostic des hémoglobinopathies chez le nouveau-né : à propos d'un cas

The diagnosis of hemoglobinopathy is based on a range of arguments: clinic, results of a blood count, the haemoglobin study and possibly a genetic study of the globin chains. The interpretation of these profiles can be complicated, especially in newborns due to the ontogenesis of globin genes. The clinical impact can range from simple microcytosis without anemia to severe anemia requiring iterative transfusions and various clinical symptoms depending on the number and type of chains produced. Knowledge of a hemoglobin pathology remains essential because of the possible transmission and combination of these anomalies to offspring.

Le diagnostic d'une hémoglobinopathie repose sur un faisceau d'arguments : la clinique, les résultats d'une numération formule sanguine, l'étude de l'hémoglobine et éventuellement une étude génétique des chaînes de globines. L'interprétation de ces profils obtenus peut être compliquée, en particulier chez le nouveau-né du fait de l'ontogénèse des gènes de globines. Le retentissement clinique peut aller de la simple microcytose sans anémie à une anémie sévère nécessitant des transfusions itératives et divers symptômes cliniques selon le nombre et le type de chaînes produites. La connaissance d'une pathologie de l'hémoglobine reste néanmoins essentielle du fait de la transmission et de la combinaison possible des anomalies à la descendance.

Fatal septic shock caused by Capnocytophaga canimorsus diagnosed by 16S rRNA gene sequencing.

Introduction: Capnocytophaga canimorsus is a commensal bacterium found in the saliva of dogs and cats. In most cases C. canimorsus causes local infection resulting from bite-wounds, scratches or licks but severe forms can occur. The following case describes a severe and rapidly fatal sepsis and disseminated intravascular coagulation with no evidence of bite in a patient without obvious cause of immunosuppression, diagnosed by polymerase chain reaction and 16S rRNA gene sequencing. Case report: Herein we present a rare case of a 39-year-old man who was taken care of by the emergency medical service for faintness, fever and chills associated with generalized mottling. Despite critical care management and broad-spectrum antibiotherapy, the patient presented an irrepressible shock with disseminated intravascular coagulation and multiple organ failure. He died during the night. The initial etiological assessment was negative but rod-shaped inclusions could be observed in his blood. A pan-bacterial polymerase chain reaction targeting part of the gene encoding 16S ribosomal ribonucleic acid (rRNA) was carried out directly on blood cultures; the sequencing identified Capnocytophaga canimorsus. Conclusions: This observation illustrates the potential severity of C. canimorsus infection even in a patient without neither obvious causes of immunosuppression nor evidence of bite. The presence of intracellular bacillary forms on the blood smear is an important information which should lead to performing a polymerase chain reaction and 16S rRNA gene sequencing.

Highly Diversified Pandoraea pulmonicola Population during Chronic Colonization in Cystic Fibrosis.

Several environmental bacteria are considered as opportunistic pathogens in cystic fibrosis (CF) and are able to persistently colonize the CF respiratory tract (CFRT). Beside Pseudomonas aeruginosa and Burkholderia cepacia complex, Pandoraea spp. are defined as pathogenic. During chronic colonization, adaptive evolution and diversified population have been demonstrated, notably for P. aeruginosa. However, the persistence of Pandoraea in the CFRT remains largely unexplored. We studied genomic and phenotypic traits of Pandoraea pulmonicola isolates successively recovered from the airways of a single CF patient and relate the results to qualitative and quantitative evolution of other cultivable pathogens and to patient clinical status. A total of 31 isolates recovered from 18 sputum samples over a 7-year period in a single CF patient were studied. Genome dynamics was assessed by pulsed-field gel electrophoresis, ERIC-PCR fingerprinting and 16S rRNA gene PCR-temporal temperature gel electrophoresis. Phenotypic features included antimicrobial susceptibility, motility, biofilm production, and virulence in Caenorhabditis elegans model. Variability was observed for all the characteristics studied leading to highly diversified patterns (24 patterns) for the 31 clonally related isolates. Some of these modifications, mainly genomic events were concomitantly observed with CFRT microbiota composition shifts and with severe exacerbations. The diversity of P. pulmonicola population studied, observed for isolates recovered from successive samples but also within a sample suggested that existence of a diversified population may represent a patho-adaptive strategy for host persistence in the heterogeneous and fluctuating CFRT environment.

Atypical hemolytic uremic syndrome triggered by varicella infection.

Varicella Zoster Virus (VZV) is a well-known virus that belongs to the Herpesviridae family which induces a self-limited disease except in specific cases in particular among stem cell transplant patients. This virus is not known however to trigger atypical Hemolytic Uremic Syndrome (aHUS). Here we report the case of a six-year-old boy who was hospitalized with fever and abdominal pains associated to pruritic and vesicular rash, thrombocytopenia and acute renal failure. He was diagnosed with aHUS precipitated by varicella virus. He was treated by an association of antimicrobials against potential superinfections, plasmapheresis and eculizumab for curative aHUS treatment. This was effective but after 6 months the kidney function remained poor. The current case describes an aHUS associated to varicella infection as demonstrated by the simultaneous occurrence of the viral infection and aHUS manifestations. Apart from typical Hemolytic Uremic Syndrome which is triggered by bacteria mostly Shiga toxin producing Echerichia coli and Streptococcus pneumoniae or Shigella, aHUS may be linked to viral infections such as HIV, EBV and enteroviruses, but very rarely by varicella. This case highlights a possible even rare complication of varicella infection a very common childhood disease. This complication could be avoided by to anti-VZV vaccination.