Response and remediation actions following the detection of Naegleria fowleri in two treated drinking water distribution systems, Louisiana, 2013-2014

Naegleria fowleri causes the usually fatal disease primary amebic meningoencephalitis (PAM), typically in people who have been swimming in warm, untreated freshwater. Recently, some cases in the United States were associated with exposure to treated drinking water. In 2013, a case of PAM was reported for the first time in association with the exposure to water from a US treated drinking water system colonized with culturable N. fowleri. This system and another were found to have multiple areas with undetectable disinfectant residual levels. In response, the water distribution systems were temporarily converted from chloramine disinfection to chlorine to inactivate N. fowleri and reduced biofilm in the distribution systems. Once >1.0 mg/L free chlorine residual was attained in all systems for 60 days, water testing was performed; N. fowleri was not detected in water samples after the chlorine conversion. This investigation highlights the importance of maintaining adequate residual disinfectant levels in drinking water distribution systems. Water distribution system managers should be knowledgeable about the ecology of their systems, understand potential water quality changes when water temperatures increase, and work to eliminate areas in which biofilm growth may be problematic and affect water quality.

In search of a method: permanent disability assessment revisited

How workers are compensated for the permanent consequences of their workplace injuries remains a hotly contested subject. The spreading misuse of the AMA Guides as the sole determinate of permanent disability has intensified the debate. This commentary highlights critical issues surrounding the AMA Guides. Finally, a restatement of the principles recommended for the assessment of permanent disability is set forth.

Long-term effects of polytetrafluoroethylene injected into the rat bladder submucosa

OBJECTIVE

The use of polytetrafluoroethylene (PTFE) paste in the lower urinary tract for the treatment of vesicoureteral reflux or urinary incontinence is increasing. Its use remains controversial and the long-term consequence of this substance injected into the lower urinary system of humans is largely unknown. When injected into the bladder submucosa, PTFE paste has been shown to elicit a foreign body reaction with chronic inflammation and possibly granuloma formation. Whether these inflammatory changes result in neoplastic changes over the long term has yet to be determined. The purpose of this study was to evaluate histologically the potential for submucosal PTFE paste to induce bladder neoplasia in a rodent model, realizing that others have shown an increased tendency for such alloplastic materials to produce sarcomas in these animals.

METHODS

Sixteen experimental animals and 4 control animals were sacrificed at various time intervals and evaluated for systemic and local tumor formation following submucosal injection of PTFE paste in the bladder. A time well beyond the equivalent of the latency period believed to be necessary for the induction of tumors in humans (15 months) was evaluated.

RESULTS

On sacrifice, histologic changes consistent with encapsulation and chronic inflammation were evident, but there was no evidence of either epithelial or sarcomatous tumor formation.

CONCLUSIONS

A quiescent foreign body reaction occurs when injecting PTFE into the bladder submucosa of rodents. Urologic use of PTFE has never been proven to induce tumors in humans or animals.