Bites by Xenodon merremii (Wagler, 1824) and Xenodon neuwiedii (Günther, 1863) (Dipsadidae: Xenodontini) in São Paulo, Brazil: a retrospective observational study of 163 cases

Despite the biological relevance and abundance of non-front-fanged colubroid snakes, little is known about their medical significance. Here, we describe the clinical, epidemiological, and biological aspects of bites by two colubroid species. We retrospectively analyzed cases of Xenodon merremii and Xenodon neuwiedii bites in which the offending snake was clearly identified. Analyses included variables related to the snake and the patient, including demographic data, clinical findings, and treatments. Of the 163 cases, 123 were bites by X. merremii and 40 by X. neuwiedii. Most bites occurred in spring and summer, predominantly during the daytime. Most offending snakes were female. Bites by X. merremii juveniles were more frequent in autumn than in other seasons, whereas those by X. neuwiedii adults were in the summer. Hands and feet were the most frequently affected regions, with no significant difference between upper and lower limbs bitten by either X. merremii or X. neuwiedii. The main clinical findings were pain, transitory bleeding, erythema, and local edema. Local edema was proportionally more frequent with X. neuwiedii bites than with X. merremii bites. No patient had extensive edema or systemic envenomation. A significant association between the snout-vent-length and transitory bleeding in bites by X. merremii, but not in those by X. neuwiedii, was identified. Whole blood clotting tests were normal in all tested patients (62 cases). Sixteen patients were incorrectly treated with anti-Bothrops antivenom. In conclusion, most accidents caused by X. merremii and X. neuwiedii present mild local symptomatology. These snakes can be mistaken for lance-headed vipers, and some bites present symptoms that resemble mild bites by Bothrops sp. Physicians should be aware of X. merremii and X. neuwiedii bites to avoid unnecessary patient distress and overprescription of antivenom.

Sabiá Virus-Like Mammarenavirus in Patient with Fatal Hemorrhagic Fever, Brazil, 2020.

New World arenaviruses can cause chronic infection in rodents and hemorrhagic fever in humans. We identified a Sabiá virus-like mammarenavirus in a patient with fatal hemorrhagic fever from São Paulo, Brazil. The virus was detected through virome enrichment and metagenomic next-generation sequencing technology.

Idiopathic thrombocytopenic purpura presenting as post-extraction hemorrhage.

AIM: The aim of this article is to present a case of idiopathic thrombocytopenic purpura (ITP) in order to emphasize the importance of the clinical exam since the anamnesis leads to a diagnostic hypothesis of ITP. BACKGROUND: Acute ITP is considered an autoimmune disease characterized by the production of antibodies against platelets, antigens produced by a viral infection, or a platelet sparing drug combination. These antibodies adhere to platelets and are recognized and destroyed by the reticulo-endothelial system. Consequently, the platelet count gradually diminishes and is insufficient for the maintenance of primary hemostasis. REPORT: A 77-year-old woman presented with post-extraction intermittent bleeding. The physical examination revealed discoloration of the skin, multiple petechiae, hematomas, ecchymosis of the upper lip, bruises all over the body, gingiva that bled spontaneously, and a malformed blood clot at the extraction site of tooth #44. The hematological exams confirmed the hypothesis of ITP. The patient was immediately hospitalized in the Hematology Department of a local hospital and received platelet replacement, hydration, medication, and general care. After the spontaneous bleeding stopped, the malformed clot was removed using alveolar curettage along with a thorough cleaning of the extraction site with a 0.9% saline solution before suturing the wound and prescribing medication. After the sixth day of hospitalization, the patient presented with the following results: Hb: 12.3 mg/dL, Ht: 36.1%, and PC: 87,000 mm3. The patient was then discharged and was placed under outpatient follow-up care. SUMMARY: The importance of the clinical exam must be emphasized since the anamnesis leads to a diagnostic hypothesis of ITP and provides the dental surgeon with an opportunity to make important systemic alterations to improve the prognosis of a patient with ITP.