Congenital asplenia and group B streptococcus sepsis in the adult: case report and review of the literature

Asplenia is associated with an increased incidence of fatal and life-threatening sepsis caused by encapsulated pathogens. Isolated congenital asplenia is a very rare condition, with only 33 cases reported in the literature. The authors report another case of this condition complicated by overwhelming Group B streptococcus sepsis secondary to paronychia that was managed successfully.     

Asymmetry of skeletal effects of Dominant hemimelia

BACKGROUND: Dominant hemimelia (Dh) is a dominant mutation that arose spontaneously in mice; Dh animals exhibit reduced numbers of lumbar vertebrae and preaxial hindlimb defects. Absence of spleen occurs in both Dh/+ and Dh/Dh animals. This study was undertaken to characterize asymmetry of skeletal defects in the Dh mouse, specifically hindlimb asymmetries in association with axial defects. METHODS: A total of 29 Dh/+ and 100 +/+ fetuses (gestational day [GD] 18) were identified by phenotype and linked DNA and their skeletons were analyzed. RESULTS: The results revealed an asymmetry of hindlimb skeletal defects in Dh/+ animals. In +/+ fetuses, the left and right tibia were symmetrical with 99.0% of the animals possessing 6 lumbar vertebrae. However, Dh/+ fetuses showed asymmetry in length of left and right tibia and a reduction to 5 lumbar vertebrae in 86.2% of animals. There was a range from mild to severe asymmetry as evidenced by direct comparison of the length of the left to the right tibia of each animal. Tibial shortening was greater on the left than the right in 65.5% of Dh/+ fetuses; only 20.7% had symmetrical tibia. Oligodactyly, defined as absence of the first or second toe, was similarly more frequent on the left. CONCLUSIONS: Asymmetry is characteristic of many human limb malformations, although analysis of the molecular basis is difficult. Therefore, Dh/+ mice, which exhibit reduced numbers of lumbar vertebrae, asymmetric hindlimb defects, and complete absence of spleen, provide an important model for studying the relationship between axial patterning and asymmetric skeletal defects.