RENO, Nev. (AP) -- Authorities on Friday were trying to determine whether a Northern California man's anger over complications he suffered from a 2010 surgery prompted him to go on a shooting rampage at a Nevada urologist's office, killing one doctor and critically wounding another before committing suicide.
Reno Police Lt. William Rulla said detectives were working to obtain Alan Oliver Frazier's medical records to learn more about his physical and mental health.
Frazier, 51, made it clear in a suicide note that he had planned the attack and that his "focus was on the physicians at the specific office," Rulla said. Police recovered the note at Frazier's home.
Investigators have declined to specify the kind of surgery he had or say whether the doctors he targeted had anything to do with it.
But a couple who lived across the street from Frazier at Lake Almanor, about 130 miles north of Reno, said the operation he had was a vasectomy. They also said Frazier frequently posted complaints in an online chat group about the pain he suffered from what he claimed was a botched surgery.
An international expert in men's reproductive health care said that while it's uncommon, some men experience pain more than two years after a vasectomy.
Neighbor Mario Tognotti told The Associated Press on Friday that Frazier told him and his wife that he sought help from doctors for his pain and had approached a lawyer about the situation. Tognotti declined to comment further.
His wife, Jari Tognotti, told the Reno Gazette-Journal in an email Thursday that Frazier encouraged friends to learn more about the kind of painful allergic reactions that men like him sometimes suffered as a result of vasectomies. She said it involved "immune-type reactions while their bodies are trying to absorb the sperm."
Dr. Paul Turek, president of the Society of Male Reproduction and Urology, said that while vasectomies remain among the safest forms of permanent contraception, there are potential short- and long-term side effects. He declined to comment on Frazier's case, but noted about 60 to 70 percent of men who undergo vasectomies develop an allergy to their sperm in the form of "antisperm antibodies."
Turek also said it's rare but possible to experience pain more than two years after a vasectomy.
"Developing over time can be a low-grade discomfort in the scrotum that's basically relieved by reversals because it's due to congestion that causes back pressure," Turek told the AP.
Any sperm allergy appears to be localized to the immune systems on reproductive tracts, he said, and antisperm antibodies have not been shown conclusively to have any significant effect on other organs.
"Unless you conceive, I don't know of any well-described diseases associated with sperm allergies," he said, adding it is difficult to measure exactly how the immune system responds to a vasectomy.
Rulla said authorities were aware that Frazier claimed he was "having adverse symptoms" from his surgery, and they were in the process of securing his full medical records to determine the nature of the operation and his claims.
Witnesses told investigators that Frazier said during the attack that he was looking for physicians, not patients. He entered the third-floor office at about 2 p.m. Tuesday with the shotgun he used to kill Dr. Charles G. Gholdoian, 46, president of Urology Nevada; critically wound Dr. Christine Lajeunesse; and seriously injure Shantae Spears, who was accompanying a relative on an office visit.
Police have declined to comment on whether they've uncovered any evidence of mental health problems in Frazier's past. City spokeswoman Sharon Spangler said Friday police would have no further comment before Monday.
Frazier's former fiancee, Stephanie Wright-West, has told the AP that Frazier took medication for depression when they were together in the mid-1990s. She also said friends once talked him out of killing himself when they found him in a truck in the mountains with a gun.
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