WHY WE GET INFECTIONS

by Steven Goldsmith MD

WHY WE GET INFECTIONS

by Steven Goldsmith MD

The rapid slapping of rubber soles and the rumbling of casters across linoleum aroused me from the notes I was scribbling in a charting cubicle. I trailed uniformed attendants as they raced a body atop a gurney across the emergency room into a vacant bay. The 13-year-old girl had collapsed while laboring over Spanish homework on her bed. In shock, Erica (not her real name) struggled to retain consciousness by a millimeter.

Initially the cause of her fever and feeble blood pressure evaded diagnosis. But an unusual sign on my physical exam spilled the beans—pulsus paradoxicus, an abnormal reduction of blood pressure when she inhaled. Supporting this finding, a chest film displayed an enlarged heart image while her blood revealed an elevated neutrophil count. The results implicated a likely infection of her pericardium, the lining around the outside of the heart. Fluid that the infection generated was compressing her heart and compromising its function.

After I plunged the large needle into her chest just over her heart, I withdrew pus. On microscopic exam the pus swarmed with diplococci, bacteria shaped like two conjoined balls. Bingo! I started Erica immediately on massive doses of IV penicillin. She survived, barely. Subsequently the lab confirmed her diagnosis: meningococcal pericarditis. (Yes, that meningococcus, feared perpetrator of meningitis.)

Erica’s recovery delighted me. I congratulated myself. Wasn’t I hot stuff! After all, my performance represented the apotheosis of diagnostic acumen that my medical school, Columbia, had prized. Even as we learned to manage the pedestrian ailments—pneumonia, diabetes, arthritis, heart failure, peptic ulcers—we yearned most of all to earn accolades, to trigger gleams in preceptors’ eyes by spotting the signs and symptoms of esoteric disease like the pulsus paradoxicus.

According to our training, Erica’s problem was meningococcal pericarditis, period. I did not yet comprehend that this diagnostic label implied questions that none of us could answer—questions bearing as much importance as her official diagnosis.

Almost no one contracts meningococcal pericarditis. In the practice of medicine, its rarity is comparable to the sighting of a woolly mammoth pirouetting across the Golden Gate Bridge. Then why did it afflict an outwardly healthy adolescent? Why Erica? What rendered her vulnerable, not just to any illness like the flu or a stomach bug but to this one in particular? Since a meningococcal infection is contagious, why did none of her classmates or relatives contract it? What protected them, or me? What could have protected her? I could not answer these conundrums for years. Until I understood that they coalesced into a central question: what was the problem to be treated? That night in the E.R. 53 years ago I thought it was a bacterial infection. How wrong I was.

Here is a clue to the correct answer. According to the National Institutes of Health, 5-10 percent of the general population ordinarily carry the bacterium Neisseria meningitidis, the “cause” of meningococcal infections such as Erica’s, in their nose and throat without symptoms of illness. But the prevalence of such carriers can rise as high as 40-90 percent among people living in close quarters such as military recruits. As carriers, they remain free of meningococcal illness despite sharing their respiratory tract with such terrifying creatures. (Similarly, 16 percent give or take of schoolchildren are carriers of the Group A streptococcus, the reputed cause of strep throat and its complications.) This suggests the following: what determines whether someone sickens from a meningococcal infection is not the microbe but the individual’s resistance. This is true of almost all infections. What sickened Erica was not a bacterium per se but a deficiency in her resistance that rendered her body vulnerable to bacterial proliferation.

We live within a sea of germs, including potential killers. Except in deliberately sterile environments, they are everywhere. Medicine’s dependence upon antimicrobial drugs as its major weapons (along with vaccines) against infection reflects an attribution of blame to the wrong culprits. Erica’s fundamental problem was not the meningococcus; it was whatever rendered her vulnerable to it. When, and only when, my profession devotes itself to the strengthening of the self-protective and self-healing resources of whole people instead of warring against germs will we be truly safer from such threats.

Be well.