TRENTON, N.J. – A congressman investigating worsening shortages of hospital drugs is demanding that secondary drug distributors reveal where they’re getting scarce, lifesaving medicines — and explain the huge markups they charge hospitals.

Letters from a House committee cite an Associated Press report that the shortages are responsible for at least 15 patient deaths and that secondary distributors are selling drugs for chemotherapy, anesthesia and infections for hugely inflated prices, in extreme cases up to 80 times the normal price.

Rep. Elijah E. Cummings, the ranking Democrat on the House Oversight and Government Reform Committee, has given five distributors — companies that hospitals say have been offering them hard-to-find drugs at dramatic markups — two weeks to answer his questions. The questions cover where the distributors are buying these drugs, what their profit is and how much their executives are being paid.

“For people to be taking advantage under these circumstances, it ought to be criminal,” Cummings told the AP.

There is no federal law against price gouging on medicine. Cummings said he’s trying to learn as much as possible about the causes of the shortages and the high prices. He said his staff has found that big markups mainly are for “life-or-death drugs.”

The Food and Drug Administration says the biggest cause of the shortages is manufacturing-quality problems that cause drugmakers to shut down production while they make improvements.

The number of new drug shortages reported this year has hit 213, two more than the record set for all of last year, according to the University of Utah Drug Information Service, which tracks the shortages. The total is three times the roughly 70 shortages per year from 2003 to 2006. And dozens of shortages from before this year still are not resolved.