A case controlled study examining the bladder microbiome in women with Overactive Bladder (OAB) and healthy controls

To characterise the microbiome in healthy women with no bladder symptoms and to compare this to the bladder microbiome in patients with overactive bladder syndrome (OAB).

MSU specimens from 63 women with OAB were compared to urine from 35 controls. Urine was centrifuged and the resulting sediment pellet was re-suspended in supernatant and plated under aerobic conditions for 48h and anaerobic conditions for 7days. Each morphologically distinct colony was purity plated. Bacterial colonies were lysed and polymerase chain reaction undertaken to amplify the 16s ribosomal RNA gene. This DNA was purified and sequenced allowing identification of bacterial genera.

The mean number of different bacterial genera was 5.0 in both controls and OAB patients (p=0.99). The uropathogenic bacteria Proteus (P=0.01) was more commonly isolated from women with OAB. The genus lactobacillus was present less commonly in urine from OAB patients when compared to urine taken from controls (p=0.02). Overall the most commonly grown bacteria were staphylococcus (grown in 59% of samples), streptococccus (51%), corynebacterium (37%) and lactobacillus (28%). A total of 95 different genera were identified from the urine samples.

The female human bladder has a diverse microbiome with stastistically significant differences between bacterial species present in OAB patients and controls.