Tuberculosis: An Old Disease Returns
Recent experience has again reminded me that many diseases once believed to be on their way to eradication must not be forgotten, as they may resurface with a vengeance. I had been reminded of this already in 2001 when our hospital took care of several patients exposed to anthrax. We quickly became “experts” on a disease none of us had in fact ever seen. More currently, however, another disease has demonstrated its ability to rise from its downward spiral. Although still a major problem throughout the world, and unfortunately a growing problem once again in the United States, tuberculosis may present in many strange and atypical ways, not always as a pulmonary problem as we have become accustomed to thinking. It may masquerade as another illness, especially in the older patient population, and may not be detected until late in its course. This week alone I encountered three such cases, amazing as that may seem.
The first was an 86-year-old gentleman who was in excellent health, active, and living with his daughter. He complained of periodic back pain for many months and took analgesics to manage his discomfort. He thought he had some form of musculoskeletal problem and dismissed it as unimportant as long as he could. He remained active until the pain grew too intense. Despite no other symptoms, on further evaluation, he was found to have severe “point tenderness over his vertebral body” and an abscess in his lumbar vertebrae was eventually diagnosed. He was initially placed on antibiotics. After further review and consultation, the abscess was drained and to everyone’s surprise revealed a diagnosis of Mycobacterium tuberculosis. Yet another review noted that he had some old granulomatous disease in the lungs, but no other acute findings were identified. His course was complicated by transient weakness of his lower legs, believed to be the result of a cord compression by the abscess, although this improved with bed rest. He currently remains on triple anti-tuberculosis therapy and is being followed not only by an internist but also by an infectious disease specialist and neurosurgeon.
The second patient was a 66-year-old man with a history of alcohol use and a diagnosis of cirrhosis. He presented with an acute increase in abdominal girth and diffuse abdominal discomfort. He was assumed to have a worsening of his chronic liver disease and ascites. He denied recent alcohol use, and his liver function tests were without change. As he was growing increasingly short of breath, a peritoneal tap was done to remove fluid. To everyone’s surprise, an exudate was found and M. tuberculosis was identified.
The third patient, also a man in his 60s, was known to have had HIV infection for a number of years. He was doing well on his antiretroviral medications but presented with increasing lethargy and dizziness on standing. He was found to have some electrolyte abnormalities and eventually was diagnosed as having adrenal insufficiency. Preliminary reports of his blood cultures were positive for tuberculosis, species not yet identified. Although tuberculosis may in fact be responsible for his adrenal problem, in this case, many other causes are possible and the work-up is still in process. This case has once again brought to the forefront another example of the potential impact that tuberculosis can have on extrapulmonary sites.
Tuberculosis is one of the oldest identified human diseases and remains the leading cause of death worldwide from a single infectious agent. As most are aware, it may remain dormant for many years only to resurface during times of declining immunocompetency. HIV infection, malnutrition, steroid use, and malignancy are frequent underlying causes. Advanced age, however, must also be considered a risk factor with age-prevalent illness, age-related changes in the immune system, and a greater chance of exposure due to increased prevalence of this disease also predisposing risk factors. Data from older persons living in nursing homes suggest a 200-fold increase in tuberculosis reactivation as compared to similarly aged individuals living in the community. We clearly can expect to see the number of new cases of tuberculosis increase as our population ages. This disease continues to evolve as a greater public health risk in this country. Unfortunately, our medical community has become less suspicious of tuberculosis because the number of new cases in the U.S. was on the decline for many years.
Most physicians remember hearing about extrapulmonary manifestations, but few recent medical school graduates have had sufficient experience in treating anything but pulmonary tuberculosis. Physicians must increasingly “think” of tuberculosis as a possible etiology for a wide variety of clinical problems and make sure that the “right” questions are asked and appropriate diagnostic tests ordered. Another disease of old has awoken with a vengeance. We must take steps to be prepared, including educating ourselves and relearning what many of us have unfortunately forgotten or never knew.
Steven R. Gambert, MD, AGSF Editor-in-Chief, Clinical Geriatrics Send comments to Dr. Gambert at firstname.lastname@example.org