Evidence for the ‘Good Genes’ Model: Association of MHC Class II DRB Alleles with Ectoparasitism and Reproductive State in the Neotropical Lesser Bulldog Bat, Noctilio albiventris

The adaptive immune system has a major impact on parasite resistance and life history strategies. Immunological defence is costly both in terms of immediate activation and long-term maintenance. The ‘good genes’ model predicts that males with genotypes that promote a good disease resistance have the ability to allocate more resources to reproductive effort which favours the transmission of good alleles into future generations. Our study shows a correlation between immune gene constitution (Major Histocompatibility Complex, MHC class II DRB), ectoparasite loads (ticks and bat flies) and the reproductive state in a neotropical bat, Noctilio albiventris. Infestation rates with ectoparasites were linked to specific Noal-DRB alleles, differed among roosts, increased with body size and co-varied with reproductive state particularly in males. Non-reproductive adult males were more infested with ectoparasites than reproductively active males, and they had more often an allele (Noal-DRB*02) associated with a higher tick infestation than reproductively active males or subadults. We conclude that the individual immune gene constitution affects ectoparasite susceptibility, and contributes to fitness relevant trade-offs in male N. albiventris as suggested by the ‘good genes’ model

Diagnosis of anterior cervical spinal epidural abscess by US and MRI in a newborn.

A 10-day-old girl who initially presented with fever developed over five days a complete paresis of both upper arms and swallowing difficulty. After emergency drainage of a retropharyngeal abscess, cervical US demonstrated a cervical anterior epidural mass compressing the cord. MRI confirmed the diagnosis of spinal epidural abscess secondary to C4-C5 spondylodiscitis. Surgical removal of the abscess was followed by complete disappearance of the neurologic symptoms after six months of follow-up. This is the first case of spinal epidural abscess in a newborn to be diagnosed by US and MRI preoperatively. The advantages of these non-invasive imaging modalities are discussed, and compared to myelography