Is that a rash on a toddler’s tummy or just evidence that he’d gotten into a box of magic markers?

The difference may be obvious to doctors, but not always to concerned parents whose first instincts are to rush the child to the nearest walk-in clinic.

In honour of April Fool’s Day, an app that has been described as “Instagram for doctors” is sharing photos of medical “symptoms” that didn’t fool physicians.

Figure 1, a mobile app co-founded by a Canadian critical care physician, Dr. Joshua Landy, allows medical professionals around the world to upload photos of their patients’ symptoms, discuss cases and seek their colleagues’ opinions.

For April Fool’s Day, Figure 1 rounded up some posts that, at first glance, may have looked worrisome, but turned out to be nothing more than rubbed-off markers, dye or even candy.

In one case, a very young child with blue lips – a potential sign of lack of oxygen in the blood -- had merely eaten Nerds.

LIPS

(Source: Figure 1)

Another healthcare professional posted a photo of a bright red urine sample that looked alarming, but turned out to be a case of “beeturia.” The patient had eaten a packet of beetroot chips two hours before the urine sample was produced.

Urine     

(Source: Figure 1)                                                                                               

And the culprit behind an apparent pink rash on a toddler’s belly turned out to be a brightly coloured marker.

Rash

(Source: Figure 1)

Anyone who downloads Figure 1 on their iOS or Android devices can view the photos, but users must be "verified" as medical professionals before they're allowed to comment or upload photos of their own. Figure 1 also has strict rules surrounding patient privacy and only uses photos that don’t reveal people’s identities.