High mortality due to snakebites in French Guiana: Time has come to re-evaluate medical management protocols

Bothrops atrox and Bothrops lanceolatus Venoms In Vitro Investigation: Composition, Procoagulant Effects, Co-Factor Dependency, and Correction Using Antivenoms

Bothrops venoms are rich in enzymes acting on platelets and coagulation. This action is dependent on two major co-factors, i.e., calcium and phospholipids, while antivenoms variably neutralize venom-related coagulopathy effects. Our aims were (i) to describe the composition of B. atrox and B. lanceolatus venoms; (ii) to study their activity on the whole blood using rotational thromboelastometry (ROTEM); (iii) to evaluate the contribution of calcium and phospholipids in their activity; and (iv) to compare the effectiveness of four antivenoms (Bothrofav™, Inoserp™ South America, Antivipmyn™ TRI, and PoliVal-ICP™) on the procoagulant activity of these two venoms. Venom composition was comparable. Both venoms exhibited hypercoagulant effects. B. lanceolatus venom was completely dependent on calcium but less dependent on phospholipids than B. atrox venom to induce in vitro coagulation. The four antivenoms neutralized the procoagulant activity of the two venoms; however, with quantitative differences. Bothrofav™ was more effective against both venoms than the three other antivenoms. The relatively similar venom-induced effects in vitro were unexpected considering the opposite clinical manifestations resulting from envenomation (i.e., systemic bleeding with B. atrox and thrombosis with B. lanceolatus). In vivo studies are warranted to better understand the pathophysiology of systemic bleeding and thrombosis associated with Bothrops bites.

[Overview of infectious and non-infectious diseases in French Guiana in 2022]

Source of many myths, French Guiana represents an exceptional territory due to the richness of its biodiversity and the variety of its communities. The only European territory in Amazonia, surrounded by the Brazilian giant and the little-known Suriname, Ariane 6 rockets are launched from Kourou while 50% of the population lives below the poverty line. This paradoxical situation is a source of health problems specific to this territory, whether they be infectious diseases with unknown germs, intoxications or chronic pathologies.Some infectious diseases such as Q fever, toxoplasmosis, cryptococcosis or HIV infection are in common with temperate countries, but present specificities leading to sometimes different management and medical reasoning. In addition to these pathologies, many tropical diseases are present in an endemic and / or epidemic mode such as malaria, leishmaniasis, Chagas disease, histoplasmosis or dengue. Besides, Amazonian dermatology is extremely varied, ranging from rare but serious pathologies (Buruli ulcer, leprosy) to others which are frequent and benign such as agouti lice (mites of the family Trombiculidae) or papillonitis. Envenomations by wild fauna are not rare, and deserve an appropriate management of the incriminated taxon. Obstetrical, cardiovascular and metabolic cosmopolitan pathologies sometimes take on a particular dimension in French Guiana that must be taken into account in the management of patients. Finally, different types of intoxication are to be known by practitioners, especially due to heavy metals.European-level resources offer diagnostic and therapeutic possibilities that do not exist in the surrounding countries and regions, thus allowing the management of diseases that are not well known elsewhere.Thanks to these same European-level resources, research in Guyana occupies a key place within the Amazon region, despite a smaller population than in the surrounding countries. Thus, certain pathologies such as histoplasmosis of the immunocompromised patient, Amazonian toxoplasmosis or Q fever are hardly described in neighboring countries, probably due to under-diagnosis linked to more limited resources. French Guiana plays a leading role in the study of these diseases.The objective of this overview is to guide health care providers coming to or practicing in French Guiana in their daily practice, but also practitioners taking care of people returning from French Guiana.

Bothrops (Fer-de-lance) snakebites in the French departments of the Americas (Martinique and Guyana): Clinical and experimental studies and treatment by immunotherapy

Snakebite envenomation is a relevant medical hazard in French Guiana and Martinique, two French territories in the Americas. All snakebite envenomations in Martinique are inflicted by the endemic viperid species Bothrops lanceolatus, whereas Bothrops atrox is responsible for the majority of snakebites in French Guiana, although other venomous snake species also occur in this South American territory. This review summarizes some of the key aspects of the natural history of these species, as well as of their venom composition, the main clinical manifestations of envenomations, and their treatment by antivenoms. B. atrox venom induces the typical set of clinical manifestations characteristic of Bothrops sp. venoms, i.e., local tissue damage and systemic alterations associated with coagulopathies, hemorrhage, hemodynamic alterations, and acute kidney injury. In the case of B. lanceolatus venom, in addition to some typical features of bothropic envenomation, a unique and severe thrombotic effect occurs in some patients. The pathogenesis of this effect remains unknown but may be related to the action of venom components and inflammatory mediators on endothelial cells in the vasculature. A monospecific antivenom has been successfully used in Martinique to treat envenomations by B. lanceolatus. In the case of French Guiana, a polyvalent antivenom has been used for some years, but it is necessary to assess the preclinical and clinical efficacy against viperid venoms in this country of other antivenoms manufactured in the Americas.

Spectrum of skin diseases in Maroon villages of the Maroni area, French Guiana

BACKGROUND

Due to their genetic characteristics and their high exposure to infectious diseases, Maroons are likely to suffer from a specific spectrum of skin diseases. However, skin disorders have never been explored in this population. We aimed to describe all skin diseases in Maroon villages of the Maroni region in French Guiana.

METHODS

This retrospective study concerned all patients who consulted in the remote health centers of Apatou, Grand-Santi, Papaichton, and Maripasoula between October 5, 2017, and June 30, 2020. We included all patients registered with a skin disorder (International Classification of Diseases) in the medical database. We excluded patients whose diagnosis was invalidated after cross-checking by a dermatologist.

RESULTS

A total of 4741 patients presented at least one skin disease, for 6058 different disorders. Nonsexually transmitted infections represented 71.6% of all diagnoses, followed by inflammatory diseases (9.8%) and bites/envenomations (4.6%). The three most frequent conditions were scabies, abscesses, and impetigo. Besides scabies, neglected tropical diseases (NTDs) were still prevalent as we reported 13 cases of leprosy and 63 cutaneous leishmaniasis. Atopic dermatitis (AD) represented only 2.5% of our diagnoses.

CONCLUSIONS

With the exception of AD, which was less frequent among Maroons, these results are similar to those previously reported in Amerindians. Therefore, a common exposure to rainforest pathogens seems to induce a common spectrum of skin diseases dominated by infections. The high prevalence of NTDs requires specific public health actions.

Characteristics of Snakebite-Related Infection in French Guiana

Wound infection is frequently reported following snakebite (SB). This study is retrospective. It was conducted in the emergency department and the Intensive Care Unit (ICU) of Cayenne General Hospital between 1 January 2016 and 31 July 2021. We included 172 consecutive patients hospitalized for SB envenoming. All patients were monitored for wound infection. Sixty-three patients received antibiotics at admission (36.6%). The main antibiotic used was amoxicillin–clavulanate (92.1%). Wound infection was recorded in 55 cases (32%). It was 19% in grade 1, 35% in grade 2, and 53% in grade 3. It included abscess (69.1%), necrotizing fasciitis (16.4%), and cellulitis (21.8%). The time from SB to wound infection was 6 days (IQR: 3–8). The main isolated microorganisms were A. hydrophila and M. morganii (37.5% and 18.8% of isolated organisms). Surgery was required in 48 patients (28.1%), and a necrosectomy was performed on 16 of them (33.3%). The independent factors associated with snakebite-associated infection were necrosis (p < 0.001, OR 13.15, 95% CI: 4.04–42.84), thrombocytopenia (p = 0.002, OR: 3.37, 95% CI: 1.59–7.16), and rhabdomyolysis (p = 0.046, OR: 2.29, 95% CI: 1.02–5.19). In conclusion, wound infection following SB is frequent, mainly in grade 2 and 3 envenomed patients, especially those with necrosis, thrombocytopenia, and rhabdomyolysis. The main involved bacteria are A. hydrophila and M. morganii.

Bleeding and Thrombosis: Insights into Pathophysiology of Bothrops Venom-Related Hemostasis Disorders

Toxins from Bothrops venoms targeting hemostasis are responsible for a broad range of clinical and biological syndromes including local and systemic bleeding, incoagulability, thrombotic microangiopathy and macrothrombosis. Beyond hemostais disorders, toxins are also involved in the pathogenesis of edema and in most complications such as hypovolemia, cardiovascular collapse, acute kidney injury, myonecrosis, compartmental syndrome and superinfection. These toxins can be classified as enzymatic proteins (snake venom metalloproteinases, snake venom serine proteases, phospholipases A₂ and L-amino acid oxidases) and non-enzymatic proteins (desintegrins and C-type lectin proteins). Bleeding is due to a multifocal toxicity targeting vessels, platelets and coagulation factors. Vessel damage due to the degradation of basement membrane and the subsequent disruption of endothelial cell integrity under hydrostatic pressure and tangential shear stress is primarily responsible for bleeding. Hemorrhage is promoted by thrombocytopenia, platelet hypoaggregation, consumption coagulopathy and fibrin(ogen)olysis. Onset of thrombotic microangiopathy is probably due to the switch of endothelium to a prothrombotic phenotype with overexpression of tissue factor and other pro-aggregating biomarkers in association with activation of platelets and coagulation. Thrombosis involving large-caliber vessels in B. lanceolatus envenomation remains a unique entity, which exact pathophysiology remains poorly understood.

Les envenimations vipérines en Guyane française

L’OMS classe l’envenimation vipérine comme pathologie négligée. Elle représente un problème de santé publique associé à des taux de mortalité et de morbidité importants. Notre objectif est de faire une mise au point sur les données récentes de la littérature sur l’épidémiologie et la prise en charge de l’envenimation vipérine en Guyane française. La Guyane est un département français presque entièrement recouvert par une forêt tropicale. Elle abrite une herpétofaune très riche comportant notamment les espèces du genre Bothrops (famille des Viperidae) qui provoquent le plus grand nombre de morsures et d’envenimations. La gestion des envenimations vipérines représente un défi de santé publique. En effet, la plupart des envenimations se produisent dans des zones rurales éloignées où l’accès aux soins est le plus compliqué, avec la présence d’un personnel médical peu formé à la prise en charge et l’indisponibilité de l’antivenin, ce qui constitue une véritable perte de chance pour les patients. En conclusion, dans un contexte d’efforts mondiaux visant à réduire l’impact des envenimations vipérines, la coopération internationale et l’engagement des autorités locales de santé et de la société civile sont nécessaires. En Guyane, la mise en place d’une véritable filière de soins et la mise à disposition de l’antivenin dans les structures sanitaires les plus isolées constitueraient un réel progrès sanitaire.

Clinical Features and Management of Snakebite Envenoming in French Guiana

The management of snakebite (SB) envenoming in French Guiana (FG) is based on symptomatic measures and antivenom (AV) administration (Antivipmyn Tri®; Instituto Bioclon-Mexico). Our study aimed to assess clinical manifestations, the efficacy, and safety of Antivipmyn Tri® in the management of SB. Our study is a prospective observational work. It was conducted in the Intensive Care Unit (ICU) of Cayenne General Hospital between 1 January 2016 and 31 December 2019. We included all patients hospitalized for SB envenoming. Our study contained three groups (without AV, three vials, and six vials Antivipmyn Tri®). During the study period, 133 patients were included. The main clinical symptoms were edema (98.5%), pain (97.7%), systemic hemorrhage (18%), blister (14.3%), and local hemorrhage (14.3%). AV was prescribed for 83 patients (62.3%), and 17 of them (20%) developed early adverse reactions. Biological parameters at admission showed defibrinogenation in 124 cases (93.2%), International Normalized Ratio (INR) > 2 in 104 cases (78.2%), and partial thromboplastin time (PTT) > 1.5 in 74 cases (55.6%). The time from SB to AV was 9:00 (5:22-20:40). The median time from SB to achieve a normal dosage of fibrinogen was 47:00 vs. 25:30, that of Factor II was 24:55 vs. 15:10, that of Factor V was 31:42 vs. 19:42, and that of Factor VIII was 21:30 vs. 10:20 in patients without and with AV, respectively, (p < 0.001 for all factors). Patients receiving Antivipmyn Tri® showed a reduction in the time to return to normal clotting tests, as compared to those who did not. We suggest assessing other antivenoms available in the region to compare their efficacy and safety with Antivipmyn Tri® in FG.

Snakebites in Suriname: Evaluation of the Protocolled Administration of Anti-Snake Venom in a Tertiary Care Setting

Venomous snakebites regularly occur in Suriname, a middle-income country located on the north coast of South America. Officially reported data on incidence and mortality are lacking. The aim of this retrospective study was to assess whether the use of our national snakebite protocol with selective administration of anti-snake venom (ASV) in patients with signs of snakebite envenoming improved clinical outcome as measured by mortality and length of stay (LOS) in the hospital. Medical records of all patients admitted at the Academic Hospital Paramaribo from 2013 to 2015, before and after the introduction of the protocol, with signs of snakebite envenoming, were reviewed for demographics, snakebite characteristics, mortality, length of hospital stay, administration of ASV, and occurrence of complications. Secondary outcome measures were the development of late complications due to a snakebite. Sixty-eight and 76 patients in 2013 and 2015, respectively, with venomous or potentially venomous snakebites were identified. One patient (1.5%) in 2013 and 29 patients (38.2%) in 2015 received ASV. In 2013 one patient died: deterioration of renal function occurred before protocolled ASV administration. No deaths were reported in 2015. There was no difference in the overall length of hospital stay between 2013 and 2015 or in the total number of late complications. In 2015, the mean LOS (±SD) for patients who did not receive ASV (n = 47) was significantly lower than that for patients who received ASV (n = 29), 2.15 ± 2.27 versus 5.31 ± 5.53 days, respectively (P = 0.001). The mean LOS (±SD) for patients who did not receive ASV in 2013 (n = 67) and 2015 (n = 47) was 4.06 ± 5.44 and 2.15 ± 2.27 days, respectively, which also differed significantly (P = 0.025). The protocolled evaluation of snakebite victims resulted in more patients being admitted to the intensive care unit and receiving ASV and a shorter length of hospital stay for the patients who did not receive ASV, and no difference in the occurrence of complications was observed in Suriname's largest hospital responsible for the acute care of snakebite victims.

Spectrum of skin diseases in Amerindian villages of the Upper Oyapock, French Guiana

Background

Due to their genetic characteristics, their isolation in rainforest areas, and their traditional way of life, Amerindian populations are likely to suffer from a specific spectrum of dermatoses. However, there are few available data on such skin disorders. Our aims were to describe all skin disorders in two Amerindian villages of French Guiana.

Methods

This retrospective study concerned all patients who consulted in the Health Centres of Camopi and Trois‐Sauts between July 1, 2017, and December 31, 2018. We included all patients classified with an ICD code linked to a skin disorder. All medical records were cross‐checked by two dermatologists to correct misclassifications.

Results

A total of 639 patients formed the study population, for 866 different skin disorders. Non‐sexually transmitted infections represented 57.6% of all skin disorders, followed by eczema (11.5%) and bites/envenomations (9.1%). Bacteria were responsible for 238 skin infections, followed by fungi (141 cases) and parasites (69 cases, including 43 scabies, nine cutaneous leishmaniasis, and two tungiasis). We reported a low prevalence of sexually transmitted infections (10 cases) and an absence of skin cancers.

Conclusions

This study revealed the absence of skin cancer in the Amerindian population of the Upper Oyapock and the important burden of infectious and animal‐related diseases. Future studies should assess a possible underestimation of sexually transmitted diseases in this area. Public health policies should target neglected diseases such as cutaneous leishmaniasis, tungiasis, scabies, and envenomations. Atopic dermatitis was a significant and unexpected cause of consultations.