Discordant Type I Preaxial Polydactyly in Monozygotic Twins on the Same Hand: A Case Report.

There are 4 types of preaxial polydactyly (PPD), and type I (PPD-I), also known as thumb duplication, is the most common. This frequently encountered condition has since been further described and classified by Wassel based on the level of duplication of skeletal anatomy. Genetic studies have localized possible candidate gene(s) for PPD types II to IV to the chromosomal region 7q36 but the current literature attributes PPD-I to isolated, spontaneous mutations typically with unilateral involvement only. Recent epidemiological studies have also suggested nongenetic causes for PPD-I including social and environmental factors. Herein, we would like to present a case of discordant PPD-I expression affecting the same hand in a pair of monozygotic twins and suggest possible reasons for this presentation because previous similar reports only had involvement of 1 child.

Microbiology of tunnelled catheter-related infections in a multi-ethnic South-east Asian patient population.

INTRODUCTION: Clinical practice guidelines recommend empiric antibiotic therapy for suspected tunnelled haemodialysis catheter-related infections (CRI), and the choice of antibiotics should be adjusted according to the local microbiological profile and antimicrobial sensitivities. We aim to describe the microbiology, antibiotic sensitivities, and clinical outcomes of CRI with tunnelled haemodialysis catheters in a multi-ethnic South-East Asian population. METHODS: Using a prospective vascular access registry, we identified 99 patients who had catheters removed for suspected or confirmed CRI (50.5% male, mean age 56.9 years) from January 1, 2007, till May 2009. We retrospectively retrieved microbiology, mortality and echocardiography data from the hospital electronic databases. RESULTS: There were 115 removal-unique cultures that yielded 75.7% Gram-positive and 24.3% Gram-negative isolates (15 removals were polymicrobial). Organisms isolated were methicillin-resistant Staphylococcus aureus (MRSA) 28.6%, methicillin-sensitive S. aureus 26.5%, coagulase-negative staphylococci 21.4%, Pseudomonas aeruginosa 10.2%, and others. Out of 8 patients who died, 7 had MRSA. Risk factors associated with mortality were Chinese race (p = 0.03), MRSA infection (p < 0.001), and older age (p < 0.001). CONCLUSION: Gram-positive isolates accounted for most tunnelled CRI and MRSA was highly associated with death. In sick patients presenting with suspected CRI, the preferred empiric antibiotic regimen should include agents active against both MRSA and P. aeruginosa.