"According to the medical journals, it is the second case in the world of a breathing complaint related to consumption of electronic cigarettes."
The US specialist medical journal Chest in April 2012 recorded the case of a 42-year-old woman who also caught pneumonia from using e-cigarettes.
Makers of e-cigarettes say they are much less harmful than tobacco and can help people give up smoking. They brushed off the case in A Coruna.
"There is no proof that this illness was linked to use of an electronic cigarette," said Alejandro Rodriguez, vice-president of the National Electronic Cigarette Association, which represents 500 companies active in Spain.
"How many people die every day from smoking? If in the 15 years that e-cigarettes have been around only two people in the world have caught light pneumonia from this product, we should say well done to it," he told AFP.