A patient said a Southern California doctor diagnosed him with "Homosexual behavior" during his first visit to the office for a check-up.

Earlier this year, Matthew Moore started seeing a new doctor who suggested he undergo a complete physical. The tests revealed he was B-12 deficient, and had high blood pressure and high cholesterol -- conditions that he called "normal for me."

When Moore, who is openly gay, went back to the Manhattan Beach office to discuss the findings, the nurse gave him the results of his physical.

Among other diagnoses, the doctor listed "Homosexual behavior (302.0)," according to medical records obtained by NBC4. "Homosexual behavior" was also listed as a chronic condition on Moore's patient plan.

"When I look up code 302.0 and its sexual deviancy or mental illness, and that code has been removed or suggested heavily not to be used since 1973," Moore said.

"My jaw was on the floor. At first, I kind of laughed, I thought, 'Here's another way that gay people are lessened and made to feel less-than,' and then as I thought about it and as I dealt with it, it angered me," Moore said.

He later returned to the office, at the suggestion of an attorney and friends, to let the doctor explain her decision. He said when asked, the doctor defended her position.

"I was dumbfounded," Moore said.

Asked how one could treat homosexuality, the doctor said that "is still up to debate" and that the sexual orientation is "still being thought of as a disease," Moore said.

Moore said he does not take issue with his sexual orientation noted on his medical chart, but he does have a problem with it listed under chronic conditions.

"Government tells us, oftentimes, that we're not equal," Moore said. "Many churches tell us that we're sinners, and now here's a medical professional telling us that we are sick. And it's gotta stop."

Unsatisfied with his doctor's response, Moore wrote a letter to the Torrance Memorial Physician Network and received an apologetic note in return, pictured at right with personal information redacted.

Moore asked for – and received – his $30 copay back.

"We fully appreciate your frustration and anger related to your experience and are committed to ensuring that such events are not repeated," Heidi Assigal, senior director of Torrance Health Association, Inc., wrote, in part.

"We would like to unequivocally state that the Torrance Memorial Physician Network does not view homosexuality as a disease or a chronic condition and we do not endorse or approve of the use of Code 302.0 as a diagnosis for homosexuality."

Moore said he does not plan to file a lawsuit against the doctor, who he asked remain anonymous to protect her reputation. He said he was inspired to tell his story to let others know that if something like this happens, "you have to speak up."

"If I was a 14-year-old in a small town in Indiana, where I'm from, and I had a doctor tell me or my parents that I was sick because they thought I was gay, it would've been very damaging," he said.

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