It’s tough to know what to do about something that doesn’t happen very often. That’s the case with hand and wrist infections from mycobacteria (a type of bacteria). Sometimes problems that seem like carpal tunnel syndrome, trigger finger, tenosynovitis, or abscesses of the wrist or hand are really caused by one of these agents.
This article was written in order to help hand surgeons identify and treat mycobacterial infections of the hand and wrist. The authors reviewed all recently published studies on this topic and report their findings. Because it’s so rare, the level of evidence is only case reports and case series.
The two most common bacterial bugs that cause hand and wrist infections include mycobacterium tuberculosis and mycobacterium marinum. Both of these bacteria are slow growing, which is one reason why they are not identified early. They don’t show up on lab studies at first. The diagnosis can be delayed six months or more, so treatment is directed elsewhere. Without the right antibiotics, the condition will not get better.
The patient shows up with wrist and hand swelling, pain, and nodules. Fever may be present. The swelling progresses (gets worse) as it spreads through the lymphatic system. There may even be pus draining from an open wound.
Antibiotics are used but not necessarily the type that will combat these specific bacteria. If the condition goes on long enough, surgery may be needed to debride (clean out) the joint. The surgeon may even have to remove some of the damaged synovium and soft tissues.
In the case of tuberculosis, there may not be signs and symptoms of lung involvement. Instead, the soft tissues and bones are affected. This is called extrapulmonary tuberculosis. There may be a previous history of pulmonary (lung) tuberculosis or HIV (human immunodeficiency virus).
Anytime tuberculosis is the underlying agent causing infection, a group of four medications must be taken for a long period of time (up to 18 months) before the bacteria can be eradicated (completely killed). Even with multidrug treatment, if the symptoms don’t improve after six to eight weeks, then surgery may be needed as well.
With hand/wrist infections from mycobacterium marinum, there is often a past history of exposure to fish (e.g., fish tank or aquarium, sushi chef preparing fish, contact with river water) or contaminated water.
As with tuberculosis, patients infected with this type of bacteria can go months to years without an accurate diagnosis. Some even have multiple surgeries before the tissue cultures are positive for the bacteria and the correct antibiotic is given.
There are other types of bacteria (e.g., M. kanasaii, M. leprae, M. abscessus, M. arupense) that can cause similar hand/wrist problems. Again, these cases are rare. Diagnosis is delayed and treatment with multiple drugs is required before symptoms resolve.
Most of the patients in the case series who were infected by other types of mycobacteria were immunocompromised. That means they had some other disease, illness, or condition that had weakened their immune systems. For example, one woman had a long history of psoriatic arthritis. Another patient had rheumatoid arthritis. Others had a history of diabetes, organ transplantation (taking immune suppressing drugs), HIV-positive, and tuberculosis.
In summary, successful treatment of rare hand/wrist infections requires accurate diagnosis. It may be necessary to retest tissue cultures many times before the growing organism shows itself and the specific antibiotics can be used.
The authors advise physicians to suspect mycobacterium when patients don’t respond to the first course of antibiotics. Risk factors such as contact with fish, past history of tuberculosis, and current immunocompromise or immune deficiency are additional red flags.
When surgery is done, hand therapy is recommended. Case studies show that patients who do not see a therapist often end up with a stiff hand and loss of function. With splinting and exercises, range-of-motion is more likely to be restored. Return of normal grip strength and full use of the wrist, hand, and fingers is the final outcome of therapy.