Nancy Welch wasn’t taking any chances. For several weeks this summer, she walked around her house clutching her cellphone, prepared in case she again had to dial 911. The memory of her terrified 13-year-old son racing down the stairs of their Northern Virginia home unable to breathe remained uppermost in her mind.

At night she slept on a blow-up mattress on the floor next to Joseph, the youngest of her three children, jolting awake whenever he gasped for breath and vomited sticky mucus, his lips briefly turning blue. Although her son quickly went back to sleep, Welch, 47, was rigidly alert. She wondered why specialists were unable to agree on a diagnosis, instead performing increasingly invasive and sometimes painful tests that seemed to lead nowhere.

Welch’s growing unease was augmented by the feeling that she knew what was wrong — a suggestion doctors had either brushed aside or failed to pursue.

“I’m just shocked that these pediatric specialists didn’t have it on their radar,” Welch said. “I’m thinking that if I hadn’t taken him to the ER, I still might not know.”

On July 3, Welch took Joseph for his annual checkup. Other than a slight cough — his mother thought he was getting a cold — he seemed fine. But the pediatrician, who heard the cough, told Welch he suspected asthma and prescribed an inhaler.

(Owen Freeman/For The Washington Post)

“I brought it home but didn’t consider using it,” Welch said. Joseph had never had asthma, and the cough seemed too minor to warrant medicine.

Three mornings later, she was shocked to see Joseph run downstairs, bug-eyed with fear because he was unable to catch his breath. Welch dialed 911 and tried to calm her panicked son — and herself. Paramedics arrived within minutes; after Welch mentioned the newly prescribed inhaler, they helped Joseph take a few puffs and advised that he use it. Within minutes, he was breathing normally.

Mother and son went back to the pediatrician that afternoon. The doctor, who reiterated his belief that Joseph had asthma, added two drugs to the medication regimen: a common antacid for reflux and azithromycin, an antibiotic to be taken for five days. “He didn’t say why he was prescribing them, and my first mistake was not to ask,” Welch said. This time, she had her son use all of the medicines the doctor prescribed.

That night, Welch recalled, her son had two or three coughing episodes. “He’d jump out of bed, cough spasmodically for about 30 seconds, spit out some sticky mucus and go back to sleep.”

Several days later, the pediatrician arranged for Joseph to see a pediatric pulmonologist.

The lung specialist, whose office was an hour away from the family’s home — an ordeal because Joseph gets carsick — concurred with the probable asthma diagnosis. A chest X-ray and a lung function test were both normal.

During that visit, Welch said, Joseph did not cough, although he tried to re-create the high-pitched wheezing, called stridor, which characterized his coughing episodes, as his mother described the sound. The pulmonologist added a second inhaled medicine and advised continuing with the anti-reflux medicine.

But instead of improving, Joseph seemed to get steadily worse. Three days later, when he began having coughing and gasping episodes every half-hour or so, Welch called the pediatrician, who told her to take him to the emergency room of Inova Alexandria Hospital.

Tale of the tape

At the hospital, Joseph, whose breathing problems had subsided, was seen by physician assistant Lynette Sandoval. A day earlier, Welch had recorded the sound of an episode on her cellphone, hoping it might provide a clue. After recounting the events of the past few days, Welch played the recording.

Sandoval said she suspected a new possibility: To her, Joseph’s high-pitched cough sounded like whooping cough, also known as pertussis, even though she had never seen a case of the once common childhood disease in her 12-year career.

“It was textbook in my mind,” Sandoval recalled. “The nocturnal, staccato cough, the desperate inspirations,” or attempts to inhale, and the fact that Joseph was largely normal between episodes all seemed to point to it, she said. But there was one factor that suggested otherwise: Joseph had been fully vaccinated against the disease, even receiving a booster shot when he was 11.

Sandoval reported her suspicion to Welch and called the pulmonologist’s partner — Joseph’s doctor was out of the office that afternoon — to discuss his treatment. He concurred, she said, with her plan to order the swab for pertussis. Several hours later, the Welches left the ER.

The following day, Welch said she played the cellphone audio for the original pulmonologist and asked whether he thought pertussis might be the problem. The specialist, she said, was adamant that it was not. He had seen pertussis in teenagers, she recalls him telling her, and “this doesn't sound like it.”

He advised continuing the medicines he prescribed. He also arranged an appointment with a pediatric ear, nose and throat specialist after Welch asked about another potential cause: Might Joseph have unknowingly swallowed one of the rubber bands he uses with his braces?

A few hours later, the ENT performed an endoscopy, threading a tiny camera down Joseph’s throat to check for anything that might be causing his cough and vomiting. Finding nothing, he recommended an evaluation by a speech pathologist in his office for possible vocal cord dysfunction.

The speech pathologist quickly rejected that possibility, Welch said, because Joseph’s problem seemed mostly to occur at night, unlike vocal cord dysfunction. By now, his mother said, her son was having as many as 15 episodes in a 24-hour period.

Doctors decided another test was in order: a bronchoscopy to inspect the inside of the lungs.

The procedure, performed under general anesthesia the following week, left Welch shaken. “It was awful seeing him waking up from anesthesia, so disoriented with his throat so irritated. And we still didn’t have an answer,” she recalled, adding that the procedure found nothing to account for his symptoms.

Welch had begun researching pertussis online and had become increasingly convinced that Sandoval’s suspicion was correct. Every day, she called the pediatrician’s office to check for the result of the pertussis test, which was inexplicably delayed.

Positive result

On July 23, the pediatrician called with the result Welch had anticipated: Joseph had whooping cough.

Pertussis produces violent coughing that can make breathing difficult — coughing so violent that it can crack a rib. Some patients also vomit sticky mucus. The airborne disease, which is highly contagious, typically surfaces about two weeks after exposure to the Bordetella pertussis bacterium. In teenagers, it can be difficult to diagnose because of its resemblance to other respiratory illnesses and because the telltale “whoop” after a cough may be absent. The disease is treated with antibiotics and usually lasts about six weeks, although the cough often lasts longer and is sometimes called “the 100-day cough.”

In the past few years, the disease, which can be fatal to infants, has experienced a dramatic resurgence. Federal health officials say that this year is on track to be the worst in 50 years; so far, nearly 31,000 cases have been reported to the Centers for Disease Control and Prevention, almost three times the number for the same period last year.

Last month, a study in the New England Journal of Medicine found that a vaccine introduced in the 1990s may be partly responsible for the resurgence. Researchers who studied a 2010-11 outbreak in California found that the effectiveness of the vaccine appears to wane significantly among children after they receive the fifth and final dose, usually by age 6. (A booster shot is recommended by CDC around age 11; in Joseph’s case, it is not clear whether the booster he received was sufficiently strong, his mother said.)

Welch’s family was put on antibiotics immediately and was told to stay home and avoid other people for five days, in case they were carriers. Joseph, who had taken the five-day course of azithromycin prescribed by the pediatrician in early July, was given a second round of the drug as a precaution.

Welch, who suspects her son might have contracted the disease at a high school graduation ceremony he attended about two weeks before he got sick, said she felt both vindicated and irritated.

“I told my family, ‘Mom was right!’ ” she said, “but my first thought was ‘How did all these people miss it? Why didn’t the pediatrician swab him, instead of pushing asthma? Why did we have to go through all that wasted effort and putting my child under procedures he didn’t have to go through?’ If this had been an obscure childhood disease, I would have understood them missing it — but I’m shocked these pediatric specialists didn’t have it on their radar” since the surge in pertussis has been widely publicized in the past year.

Welch said she was so grateful to Sandoval for listening to her that she called to thank her. But when she asked the lung doctor whether he would have done anything different, he told her no.

Sandoval speculates that the diagnosis may have been missed because some of Joseph’s doctors did not hear his tortured breathing, as she did. “The recording was key,” she said, “because not everybody is going to use terminology in the same way to describe it.” And she speculated that some doctors may have been misled because Joseph had been fully vaccinated.

Joseph is fully recovered, his mother said; his cough disappeared after 100 days. Looking back, Welch said she thinks she should have asked the pediatrician why he was prescribing an antibiotic and sought the guidance of an infectious-disease specialist before agreeing to invasive and expensive tests.

Mostly, she said, she remains puzzled. “Why, with whooping cough making a resurgence, wasn’t it given any serious consideration?”

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