Twins, their plumbing, and an old painting

Twin-twin transfusion syndrome (TTTS), in which one developing fetus funnels extra blood to the other to the detriment of both, was first described in 1875 after some clever observations by a German physician named Friedrich Schatz. It happens in identical twins (and triplets) that share a placenta, and the trouble lies in abnormal blood vessels that flow one way from the "donor" twin to the "recipient." The recipient gets extra blood, and his kidneys filter it and expel it in the form of amniotic fluid--too much amniotic fluid, in fact, to the point where the recipient's bladder and body swell up. The donor, on the other hand, loses blood volume, shrinks, and within his own sac he floats in so little fluid that he can appear stuck to the wall of the uterus on ultrasound. The survival rate is low without treatment, and good treatments are few and uncertain, though lasering the abnormal connections seems to help.

Here's an interesting side note. Fetuses that survive to be born may look a little unusual, with the donor appearing small and pale and the recipient looking reddish and rather too robust. Wikipedia's article on the syndrome displays a 1617 painting of two wizened, swaddled babies looking rather strikingly TTTS-ish. Could this be an early illustration of the disease ?

The scholarly pursuit of seeking out medical diagnoses by studying paintings and other works of art is called "diagnosing the canvas." An astonishing amount of information can be gleaned from old paintings. The New York Times has more.