This neck swelling could be anything. What one question will help narrow your differential?
Visual Case Studies Presented by Mark Silverberg, MD
A 27 y.o. African American male presents to your ED complaining of left sided neck swelling. He first noticed the mass 3 months ago which has been growing in size. It’s painless, but he is concerned about its appearance. He recalls no trauma or recent history of URI-type symptoms. He reports that he has lost almost 10lbs over the last 4 months. He specifically denies fever/chills, night sweats, cough and has no difficulty swallowing or breathing. Upon further inquiry, he reveals that he has been fairly promiscuous prior to being married 3 years ago but denies any illicit drug use and has never been tested for HIV disease.
On physical examination you see a well appearing young male who does not look acutely sick. His vital signs, including a finger stick are within normal limits. His pharynx appears pink and healthy and his lungs sound clear. He is noted to have a 4-centimeter swelling just above the clavicle along the SCM on the left side of his neck. It is slightly erythematous and firm but is non-tender and resists all attempts at mobilization. The rest of his physical is grossly unremarkable so you decide to send off some basic laboratory studies and order a CXR.
When first approaching this patient, you should think of “worst first;” Does the swelling encroach on the airway? Our patient is in no apparent distress, has no difficulty breathing and no stridor. Therefore, with the critical A,B,C’s out of the way, we can move on to correctly diagnosing our patient.
Malignancy is probably a good second thought in the vein of “worst first.” He does have weight loss, a physical examination consistent with a metastasis or lymphoma (although it is only one node) and may be HIV positive. The Lymphoma Research Foundation of America reports 10% of all patients with HIV will develop some form of lymphoma in their lifetime. He does have HIV risk factors in his sexual promiscuity although he denies IV drug use. To confirm the diagnosis of malignancy, we would need a fine needle aspiration or biopsy to look at the tissue under a microscope.
Another initial consideration may be an infectious process such as an abscess. This type of infection could reside in the superficial skin structures or deeper within the potential neck spaces. After reviewing the H & P, abscess seems unlikely for a couple of reasons. His mass is not tender or fluctuant. It has been growing for some time and has not drained or ruptured. It is also located in an area that would be uncommon for an abscess to form. However, an ultrasound and/or CT scan could help differentiate between a solid mass and a fluid/puss filled abscess.
Another infectious etiology could be simple reactive cervical adenitis. However, this is also unlikely since the mass is non-tender, not freely mobile and he denies sore throat, cough, fever, chills or other upper respiratory manifestations. The diagnosis of reactive adenitis may still be considered, but it would be a diagnosis of exclusion.
What about cat scratch disease? Localized lymphadenopathy is classic for this malady. The axilla and cervical nodes are typical sites for upper extremity cat-claw injuries. The nodes involved are typically tender and may spontaneously suppurate. Many patients also complain of non-specific symptoms such as seen in our patient. This diagnosis may be made with serological testing, PCR or fine needle aspiration. Cat scratch disease is usually self limited, but does have the potential to be life threatening for immunocompromised patients therefore, an HIV test is becoming more and more important in this case. While our patient did not report being in contact with any animals over the past few months, if the disease is still suspected, it may be prudent to send serological testing. If our patient turns out to be immunocompromised and this entity is missed, it could be devastating and therefore must be considered.
Another malady to consider is cervical tuberculous adenitis, AKA scrofula. Factors that support this diagnosis are the weight loss and the nontender, slowly enlarging presentation of the mass. Additional history may be helpful to see if this patient is at elevated risk for acquiring TB. Being immunocompromised definitely makes you more susceptible to TB but this patient does not know his HIV status. Upon further questioning, he has never been in prison or lived in a shelter but he lived in Haiti up until 6 months ago. He is coming from a country in which approximately 6% of the population is infected with the HIV virus and TB is endemic. While the patient does not seem to have many symptoms supporting the diagnosis of TB other than the mass itself and weight loss, he definitely seems to have many risk factors for TB. Although, not immediately life threatening, he would require urgent diagnosis and treatment to protect the community around him from contracting this latent mycobacterial infection.
Out patient’s labs soon arrive. The CBC appears normal with no sign of anemia or leukocytosis making any type of infectious etiology even more unlikely. The ESR is mildly elevated at 26. The chest X-ray is normal, showing no sign of active infection including tuberculosis or sarcoid which can both bring about our patient’s symptoms. What would the next step be? How about a neck CT? Yes, there are two good reasons to perform this test in the ED before the patient is discharged. The first reason is to confirm that this is definitely not an abscess, while the second is to make certain this mass is not invading or impinging upon any vital neurovascular structures. The CT with IV contrast is performed (the patient had good renal function) but demonstrated only a heterogenous soft tissue mass. What could it be? You order an HIV test, place a PPD and arrange urgent follow up with an otolaryngologist.
Two days later the ENT is kind enough to call you and confirm your suspicions. The PPD was 12mm and a final needle aspiration showed the patient to have Mycobacterium tuberculosis growing in the mass consistent with cervical tuberculous adenitis. Your HIV test was also positive. This patient had scrofula.
While uncommon, approximately 5% of patients with TB initially present with extrapulmonary manifestations of this disease. Higher incidences have been seen in HIV positive populations. Of these cases, scrofula is the most familiar manifestation of extrapulmonary tuberculosis in the Unites States accounting for 30-50% of the instances. Infection is produced through hematogenous seeding or from local extension from infected lungs, adenoids or tonsils. While our patient grew Mycobacterium tuberculosis, other causes of scrofula can rarely be encountered such as M. scrofulaceum or M. avium.
As seen in this patient, the most common presentation of scrofula includes a unilateral painless swelling of the neck that slowly enlarges over time. Pain or bilateral involvement at the time of diagnosis is possible. Young, middle aged adults are the most common individuals afflicted with a slight female predominance.
While our otolaryngologist was lucky enough to see Mycobacterium tuberculosis on an acid fast smear, this test has a much lower sensitivity than with pulmonary tuberculosis. All retrieved samples should be cultured to confirm a microscopic diagnosis. Polymerase chain reaction can also be used for rapid testing of the aspirate. Utilizing all modalities, sensitivity can range from 53-77% with specificity approaching 93%.
How should this patient now be treated once we know the diagnosis is scrofula? A 4-drug regiment should be initiated including rifampin, ethambutol, pyrazinamide and isoniazid. Surgery should not be used as initial therapy, but may be needed for excision of persistent draining wounds or for infections failing standard medical management. All patients should be followed closely by an infectious disease specialist.