Assessment of the reproduction of six collembolan species in tropical soils naturally rich in potentially toxic elements.

Laboratory ecotoxicological tests are important tools for the management of environmental changes derived from anthropogenic activities. Folsomia candida is usually the model species used in some procedures. However, this species may not be sufficiently representative of the sensitivity of the other collembolan species. This study aimed to evaluate (i) the effects of soils naturally rich in potentially toxic elements (PTE) and soil characteristics on the reproduction and survival of different collembolan species, (ii) whether the habitat function of these soils is compromised, and (iii) to what extent F. candida is representative of the other collembolan species. For this, reproduction tests with six collembolan species were conducted in 14 different samples of soils. In general, collembolan reproduction was not completely inhibited in none of the natural tested soils. Even soils with high pollution load index values did not negatively affect collembolan reproduction for most of the species. In contrast, the lowest collembolan reproduction rates were found in a visually dense soil (lowest volume/weight ratio), highlighting that soil attributes other than total PTE concentration also interfere in the reproduction of collembolans. Our results support the idea that the F. candida species might not be representative of other collembolan species and that laboratory tests to assess soil contaminations should be conducted using diverse collembolan species.

Rib osteomyelitis: a rare complication of varicella / Osteomielite de arco costal: uma complicação rara de varicela

ABSTRACT Objective: To report a case of varicella complicated by acute osteomyelitis in order to remind of a rare and potentially serious complication of a very common pediatric disease. Case description: A previously healthy 3-month-old female infant with 10-day history of varicella was admitted to the hospital for fever, groan and prostration. The initial laboratorial evaluation was compatible with bacterial sepsis. By the third day after admission, a swelling of the seventh left rib had developed. The ultrasound and scintigraphy evaluation suggested rib osteomyelitis. Blood cultures were negative. The patient completed six weeks of antibiotics with favorable clinical, laboratorial and imaging evolution. Comments: Varicella is one of the most frequent exanthematic diseases of childhood and it is usually self-limited. The most frequent complication is bacterial infection of cutaneous lesions. Osteoarticular complications are rare, and rib osteomyelitis is described in less than 1% of cases. The main route of dissemination is hematogenic, and the most frequent etiological agent is Staphylococcus aureus. The prognosis is generally good and depends on early detection and antibiotic initiation.

RESUMO Objetivo: Descrever um caso de varicela complicada de osteomielite aguda a fim de alertar para a complicação rara e potencialmente grave de uma doença muito frequente em idade pediátrica. Descrição do caso: Lactente de três meses, previamente saudável, internada por um quadro de febre, prostração e gemido, num contexto de varicela com cerca de dez dias de evolução, com avaliação inicial compatível com sepse de etiologia bacteriana. No terceiro dia de internação, observou-se uma tumefação na sétima costela esquerda. A avaliação ecográfica e cintilográfica mostraram alterações sugestivas de osteomielite de arco costal. As hemoculturas foram negativas. Recebeu antibioticoterapia por seis semanas e evoluiu favoravelmente do ponto de vista clínico, laboratorial e ecográfico. Comentários: A varicela é uma das doenças exantemáticas mais frequentes da infância, sendo habitualmente autolimitada. A complicação mais frequente é a infecção bacteriana secundária das lesões cutâneas, sendo raras as complicações osteoarticulares. O arcabouço costal é uma localização excepcional de osteomielite, descrita em menos de 1% dos casos. A principal via de disseminação é a hematogênica, e o agente mais frequente, o Staphylococcus aureus. O prognóstico é geralmente bom, quando a antibioticoterapia se institui precocemente.