Gray platelet syndrome (GPS) is an inherited disorder. Patients harboring GPS have thrombocytopenia with large platelets lacking α-granules. A long-term complication is myelofibrosis with ...pancytopenia. Hematopoietic stem cell transplant (HSCT) could be a curative treatment. We report a male GPS patient with severe pancytopenia, splenomegaly and a secondary myelofibrosis needing red blood cells transfusion. He received an HSCT from a 10/10 matched HLA-unrelated donor after a myeloablative conditioning regimen. Transfusion independence occurred at day+21, with a documented neutrophil engraftment. At day+ 180, we added ruxolitinib to cyclosporine and steroids for a moderate chronic graft versus host disease (GVHD) and persistent splenomegaly. At day+240 GVHD was controlled and splenomegaly reduced. Complete donor chimesrism was documented in blood and marrow and platelets functions and morphology normalized. At day+ 720, the spleen size normalized and there was no evidence of marrow fibrosis on the biopsy. In GPS, HSCT may be a curative treatment in selected patients with pancytopenia and myelofibrosis.
BackgroundDecompression sickness (DCS) with spinal cord involvement has an unfortunately high rate of long-term sequelae. The objective of this study was to determine the association of prehospital ...variables on the outcome of spinal cord DCS, especially the influence of the initial clinical presentation and the time to recompression.MethodsThis was a retrospective study using prospectively collected data which included divers with spinal cord DCS seen at a single hyperbaric centre study from 2010 to 2018. Information regarding dive, latency of onset of symptoms, time to recompression and prehospital management, that is, use of oxygen, treatment and means of evacuation, were analysed as predictor variables. The initial clinical severity was estimated by the score of the French society of diving and hyperbaric medicine (MEDSUBHYP). The primary end point was the presence or absence of sequelae at discharge assessed by the modified score of the Japanese Orthopedic Association.Results195 divers (48±12 years, 42 women) were included. 34% had neurological sequelae at discharge. In multivariate analysis, a MEDSUBHYP score ≥6 and a time to recompression >194 min were significantly associated with incomplete neurological recovery (OR 9.5 (95% CI 4.6 to 19.8), p<0.0001 and OR 2.1 (95% CI 1.03 to 4.5), p=0.04, respectively). Time to recompression only appeared to be significant for patients with high initial clinical severity. As time to recompression increased, the level of sequelae also increased (p=0.014).ConclusionDetermining the initial clinical severity is critical in identifying patients who need to be evacuated for recompression as quickly as possible.
Introduction
Spinal cord decompression sickness (scDCS) unfortunately has a high rate of long-term sequelae. The purpose of this study was to determine the best therapeutic management in a hyperbaric ...center and, in particular, the influence of hyperbaric treatment performed according to tables at 4 atm (Comex 30) or 2.8 atm abs (USNT5 or T6 equivalent).
Methods
This was a retrospective study that included scDCS with objective sensory or motor deficit affecting the limbs and/or sphincter impairment seen at a single hyperbaric center from 2010 to 2020. Information on dive, time to recompression, and in-hospital management (hyperbaric and medical treatments such as lidocaine) were analyzed as predictor variables, as well as initial clinical severity and clinical deterioration in the first 24 h after initial recompression. The primary endpoint was the presence or absence of sequelae at discharge as assessed by the modified Japanese Orthopaedic Association score.
Results
102 divers (52 ± 16 years, 20 female) were included. In multivariate analysis, high initial clinical severity, deterioration in the first 24 h, and recompression tables at 4 atm versus 2.8 atm abs for both initial and additional recompression were associated with incomplete neurological recovery. Analysis of covariance comparing the effect of initial tables at 2.8 versus 4 atm abs as a function of initial clinical severity showed a significantly lower level of sequelae with tables at 2.8 atm. In studying correlations between exposure times to maximum or cumulative O2 dose and the degree of sequelae, the optimal initial treatment appears to be a balance between administration of a high partial pressure of O2 (2.8 atm) and a limited exposure duration that does not result in pulmonary oxygen toxicity. Further analysis suggests that additional tables in the first 24–48 h at 2.8 atm abs with a Heliox mixture may be beneficial, while the use of lidocaine does not appear to be relevant.
Conclusion
Our study shows that the risk of sequelae is related not only to initial severity but also to clinical deterioration in the first 24 h, suggesting the activation of biological cascades that can be mitigated by well-adapted initial and complementary hyperbaric treatment.
Circulating mitochondrial DNA (mtDNA) is receiving increasing attention as a danger-associated molecular pattern in conditions such as autoimmunity or trauma. In the context of decompression sickness ...(DCS), the course of which is sometimes erratic, we hypothesize that mtDNA plays a not insignificant role particularly in neurological type accidents. This study is based on the comparison of circulating mtDNA levels in humans presenting with various types of diving accidents, and punctured upon their admission at the hyperbaric facility. One hundred and fourteen volunteers took part in the study. According to the clinical criteria there were 12 Cerebro DCS, 57 Medullary DCS, 15 Vestibular DCS, 8 Ctrl+ (accident-free divers), and 22 Ctrl- (non-divers). This work demonstrates that accident-free divers have less mtDNA than non-divers, which leads to the assumption that hyperbaric exposure degrades the mtDNA. mtDNA levels are on average greater in divers with DCS compared with accident-free divers. On another hand, the amount of double strand DNA (dsDNA) is neither significantly different between controls, nor between the different DCS types. Initially the increase in circulating oligonucleotides was attributed to the destruction of cells by bubble abrasion following necrotic phenomena. If there really is a significant difference between the Medullary DCS and the Ctrl-, this difference is not significant between these same DCS and the Ctrl+. This refutes the idea of massive degassing and suggests the need for new research in order to verify that oxidative stress could be a key element without necessarily being sufficient for the occurrence of a neurological type of accident.
Massive bubble formation after diving can lead to decompression sickness (DCS) that can result in neurological disorders. In experimental dives using hydrogen as the diluent gas, decreasing the ...body's H
burden by inoculating hydrogen-metabolizing microbes into the gut reduces the risk of DCS. In contrast, we have shown that gut bacterial fermentation in rats on a standard diet promotes DCS through endogenous hydrogen production. Therefore, we set out to test these experimental results in humans. Thirty-nine divers admitted into our hyperbaric center with neurological DCS (Affected Divers) were compared with 39 healthy divers (Unaffected Divers). Their last meal time and composition were recorded. Gut fermentation rate was estimated by measuring breath hydrogen 1-4 h after the dive. Breath hydrogen concentrations were significantly higher in Affected Divers (15 ppm 6-23 vs. 7 ppm 3-12; P = 0.0078). With the use of a threshold value of 16.5 ppm, specificity was 87% 95% confidence interval (CI) 73-95 for association with neurological DCS onset. We observed a strong association between hydrogen values above this threshold and an accident occurrence (odds ratio = 5.3, 95% CI 1.8-15.7, P = 0.0025). However, high fermentation potential foodstuffs consumption was not different between Affected and Unaffected Divers. Gut fermentation rate at dive time seemed to be higher in Affected Divers. Hydrogen generated by fermentation diffuses throughout the body and could increase DCS risk. Prevention could be helped by excluding divers who are showing a high fermentation rate, by eliminating gas produced in gut, or even by modifying intestinal microbiota to reduce fermentation rate during a dive.
Massive bubble formation after diving can lead to decompression sickness (DCS). During dives with hydrogen as a diluent for oxygen, decreasing the body's H2 burden by inoculating ...hydrogen-metabolizing microbes into the gut reduces the risk of DCS. So we set out to investigate if colonic fermentation leading to endogenous hydrogen production promotes DCS in fasting rats. Four hours before an experimental dive, 93 fasting rats were force-fed, half of them with mannitol and the other half with water. Exhaled hydrogen was measured before and after force-feeding. Following the hyperbaric exposure, we looked for signs of DCS. A higher incidence of DCS was found in rats force-fed with mannitol than in those force-fed with water (80%, 95%CI 56, 94 versus 40%, 95%CI 19, 64, p < 0.01). In rats force-fed with mannitol, metronidazole pretreatment reduced the incidence of DCS (33%, 95%CI 15, 57, p = 0.005) at the same time as it inhibited colonic fermentation (14 ± 35 ppm versus 118 ± 90 ppm, p = 0.0001). Pre-diveingestion of mannitol increased the incidence of DCS in fasting rats when colonic fermentation peaked during the decompression phase. More generally, colonic fermentation in rats on a normal diet could promote DCS through endogenous hydrogen production.
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