Problems with multi-resistant organisms? Standard measures not working out? Colleagues who’ve forgotten how to wash their hands? Here’s a group who’ve taken a military approach to room cleaning.

Thanks to Mazhar Hussein ( Microbiology On-line) for drawing our attention to this video.

Questions on Post-infectious lactose intolerance (PILI) answered:

Q. What is post-infectious lactose intolerance?

Post-infectious lactose intolerance (PILI) is a temporary loss of the ability to digest a sugar known as lactose, commonly found in milk-containing foods and drinks. PILI is a complication of common gastrointestinal infections in people who were able to digest dairy products before the start of the infection.

Q. What infections cause lactose intolerance?

The infections that have been linked to PILI are those viral, bacterial and parasitic infections that cause non-inflammatory diarrhoea i.e. infections the only cause minimal damage to the intestinal lining. These include rotavirus, Giardia intestinalis, Cryptosporidium and Cyclospora. Accurate figures are lacking, but PILI probably occurs in only a small proportion of all non-inflammatory infective diarrhoeas.

Q. Why does gastrointestinal infection cause lactose intolerance?

PILI is caused by temporary loss of the ability of the small intestine to digest dietary lactose when the lining of the small intestine becomes damaged by the infectious agent (viruses, bacteria or parasites). The temporary loss of intestinal digestive enzyme function leaves lactose intact. As a result it cannot be absorbed and stays in the intestine, keeping water with it. Bacteria normally present in the small intestine metabolise the excess lactose, producing hydrogen, methane and carbon dioxide gas. They also increase the acidity of intestinal contents. PILI is not an allergic reaction and should be distinguished from food allergies.

Q. What are its signs and symptoms?

Lactose intolerance means that consumption of milk and other lactose-containing dairy products will cause gas production, leading to abdominal discomfort, bloating, belching and flatulence. Stools may be noticeably bulky, loose and even diarrhoeal. Stool pH will be low and a hydrogen breath test, if available, may be positive.

Q. How long will it last?

Studies on rotavirus infection show that PILI lasts for an average of a few days if the gastroenteritis is mild, but may persist for much longer if there is prolonged gastroenteritis. Detailed figures are lacking for most specific infections, particularly in adults.

Q. What can be done about it?

PILI is normally a temporary condition and should improve with time even if nothing is done about it.

The options your physician can offer you include

• waiting it out (mild lactose intolerance)
• avoiding milk and other dairy products (butter, cream, ice cream, yoghurt, cheese and anything with whey products)
• using lactase dietary supplements

Symptoms should response to dietary management within days. If they persist despite these measures, further advice from your physician should be sought.

Further information

• Lactose intolerance, Wikipedia
• Diarrhoeal diseases, World Health Organization
• Lactose intolerance in infants, children and adolescents. American Academy of Pediatrics (revised 2006).

MicroGnome, 27^thJune, 2010.

Next Thursday, March 25th, there will be a talk on current and future applications of cell biology methods in clinical microbiology, with illustrations from recent infectious disease cases.  For those who can get there it will be in the Microbiology seminar room, 1st floor, L block, QEII Medical Centre, Nedlands, WA 6009 at 8am. Breakfast will be available beforehand.

This is a subject area close to the μgnome’s heart, and promises to be a significant departure from the same old, same old.

• What can a flow cytometer, confocal microscope or motorised microscope stage do for your patients?
• What might image-based reporting look like?
• Where does this leave molecular diagnostics?

You can place bets on a guest appearance by the dancing amoebas and there may even be a few parasites to FRET about. All in all, an interactive session not to be missed.

μgnome, 20th March