A court fight between one of the nation’s largest allergy clinics and one of Mecklenburg’s most respected doctors has resulted in allegations of rampant clinical errors and excessive caseloads.

Dr. Maeve O’Connor, former head of the Mecklenburg County Medical Society, has left Carolina Asthma and Allergy Center and is fighting for the right to run her own practice.

Her move has triggered a high-stakes court fight, with her old clinic alleging that she violated a “noncompete” clause in her contract.

Carolina Asthma sued O’Connor last week and she fired back with allegations that the center’s staff put patients in danger by – among other things – injecting them with the wrong medications, wrong doses and, in one case, nothing but air.

Dr. Gray Norris, the allergy center’s president, called O’Connor’s allegations of substandard care “utterly false, outrageous and defamatory.”

He acknowledged in court papers that occasional mistakes are unavoidable in a large practice with about 36,000 “patient encounters” each month.

“Most of the mistakes are minor and don’t harm patients,” Norris said in an affidavit. “On exceeding (sic) rare occasions more serious mistakes are made, but they are not systemic and are quickly addressed.”

The case provides a rare, behind-the-scenes look at the conflicts that can roil medical practices run by doctors with competing visions.

With eight offices and about 100 employees, CAAC is Mecklenburg’s largest allergy clinic. O’Connor joined the practice in 2003, and soon became one of Charlotte’s most respected doctors.

Repeatedly named to Charlotte Magazine’s peer-selected list of “top doctors,” she served last year as president of the county medical society, a professional group with more than 1,300 physician members. Patients liked her, too, and O’Connor saw significantly more of them than most other doctors at the practice.

But under the surface, tensions at the clinic simmered. O’Connor, one of 11 doctors at the practice, said in court papers that she pushed for years to correct potentially dangerous clinical problems. Things got worse in 2012, she said, and she eventually realized she could not persuade her fellow shareholders to fix the problems.

In April 2012, she came to a shareholders meeting with seven proposals for improving the clinical environment. The shareholders refused to vote on them, she said.

“That was the last straw for me,” she said in an affidavit. “I could not stay in an environment where the problems were known and ignored.”

In court papers, she cited the following incidents:

• A nurse in 2012 incorrectly told a patient she had a condition that she didn’t have – then told the patient to begin taking medication to which she’s allergic.

• The same year, a nurse injected a patient with another patient’s medication.

• A staff member gave a granola bar to a young patient with a peanut allergy – and didn’t tell the patient’s father the bar might contain peanuts. “Fortunately the patient developed only hives and itching, rather than a more severe, or even fatal, allergic reaction,” O’Connor said in her affidavit.

• A child was tested last year for peanuts, but not tree nuts, despite a request by the patient’s mother for both tests. Afterward, staff told the mother her child was free to eat nuts. The child later suffered a severe allergic reaction to salad dressing containing walnuts.

• During O’Connor’s early years with the clinic, a former lab supervisor was coming to work drunk and continuing to drink on the job. That person was responsible for mixing the medications for allergy shots. Errors mixing those drugs “can have deadly outcomes,” O’Connor said in her affidavit. The supervisor was forced to go to rehabilitation only after O’Connor threatened to quit, she said.

• A nurse in 2009 accidentally injected air into a patient, failing to realize that her syringe contained no medicine. “Fortunately this injection was into the patient’s muscle, and not into a blood vessel (which could have killed the patient from an air embolism),” O’Connor said in her affidavit.

“These are just a handful of what I am certain to be hundreds, if not thousands, of clinical and administrative errors, which put CAAC’s patients at risk,” said O’Connor, 42.

Pat Kelly, the attorney representing CAAC, said there’s nothing to substantiate that errors were as common as O’Connor described.

Kelly said he’s not aware of any malpractice suits filed against the clinic’s medical staff, or any cases in which a mistake resulted in serious injury or hospitalization.

‘Money and power’

Norris, the center’s president, contended that the practice successfully addressed problems – and that almost all the complaints O’Connor lodged in her final months involved her own patients and staff.

“It was primarily her responsibility to ensure the satisfaction of her patients and the training and performance of the staff who worked for her, not anyone else’s,” Norris said in his affidavit.

Kelly contended that what angered O’Connor most were decisions reached by her partners that reduced her income and control. “It’s money and power that drove her,” he said.

To help ensure patients got the time and attention they deserved, the clinic imposed a limit on the number of patients a doctor could see each day. But Norris asserts that O’Connor paid little heed to the 28-patient limit.

“Dr. O’Connor, the self-proclaimed champion of patients, balked at this limit and frequently ignored it so she could make more money,” Norris said in court papers. “She refused to acknowledge that her medical record charting was often deficient as a result.”

Last week, O’Connor opened a new practice – Allergy, Asthma and Immunology Relief of Charlotte – at an office in south Charlotte.

CAAC maintains that O’Connor has violated a contractual “noncompete clause,” which prohibits doctors who resign from practicing allergy or asthma care in the region for two years. O’Connor’s attorneys contend that the contract is unenforceable, partly because the center breached it by failing to provide the staff “reasonably necessary” for her to do her job.

A question of control

O’Connor said she had no desire to see more than 28 patients a day. She and the clinic apparently disagree about whether she controlled her own schedule.

No one at CAAC ever complained about the documentation in her charts until after she’d left, she said.

O’Connor said she had no staff and, like other doctors, was prohibited from dealing directly with staff problems. In later years, the doctors didn’t train or discipline the staff; in an effort to avoid micromanagement, they agreed to let the clinic’s managers do that.

Before leaving the practice, O’Connor was earning about $700,000 annually. But she objected to the suggestion that money played a key role in her decisions. She expects to earn less than a third as much working on her own. The average salary for allergy doctors is about $225,000 a year.

“I never put money before patient care, or I wouldn’t be sitting here,” she said during a tearful interview at the Charlotte offices of James, McElroy and Diehl, the law firm representing her.

‘Fix this place’

More than a dozen people – most of them former CAAC staff members and patients – have signed affidavits that support O’Connor’s assertions. They pointed to staff who gave patients the wrong shots, who were unable to draw blood, and who refused to help patients resolve medical problems.

Kelly said some who signed those affidavits were fired by CAAC, while others were friends of O’Connor.

O’Connor said she never wanted it to come to this. She cares about those who work at the center, she said, and she worries about the patients.

She recalls the day last summer when she left the practice for good: “The last thing I said to the last partner I saw … is: ‘Please fix this place.’ ”

In a hearing Monday, Superior Court Judge Hugh Lewis said he would issue a temporary restraining order to prevent O’Connor from providing asthma or allergy care at her new office, as long as CAAC posts a $250,000 bond to help cover damages if it’s later determined she can operate her new practice.

As of Friday, that bond had not been posted.