Day: October 8, 2007

What is the Differential Diagnosis of a Neck Mass?

Patient Presentation
A 2-year-old female came to clinic with sudden onset of left-sided neck swelling.
She had been well the previous evening and woke up with the swelling.
She had no pain, fever, skin rashes, mental status changes, night sweats or weight loss. She was eating and breathing normally.
She did have some rhinorrhea for the past 3 days. Her mother said that the swelling had not seemed reddened or warm to her.
The past medical history showed a healthy female with 2 previous ear infections and she was up to date on her immunizations including having one Measles-Mumps-Rubella vaccine.
The family history revealed stroke and renal abnormalities.
The review of systems was normal.
The pertinent physical exam showed temperature of 36.2° C, pulse = 108 beats/minute and respiratory rate = 32 breaths/minute.
Growth parameters were in the 10-75% with no weight loss and she was not distressed.
HEENT showed normal ears and throat. She had obvious left submandibular, subauricular, and anterior auricular swelling that covered the angle of the mandible. The swelling was confluent, firm but not hard, non-tender, non-erythematous and not warm.
She had full range of motion in the temporomandibular joint and neck.
There was no fluid seen from the salivary ducts when they were milked. There was no pain or swelling of the dental tissues.
There were shoddy anterior and posterior cervical lymph nodes. There were no supraclavicular nodes palpable.
Skin was normal with no rashes and no dimpling notable on the neck. There was no thyroid enlargement. Lung examination was negative.
The diagnosis of parotitis/sialadenitis was made. Because she was immunized and there were several enteroviruses in the community, one of these viruses was suspected as the cause.
The laboratory evaluation included mumps titres which eventually were negative.
The patient’s clinical course showed she had a low grade fever and developed a rash on her palms and soles later the first day, but she had slow resolution of all symptoms over 7 days.

Discussion
Sialadenitis is swelling of the salivary glands, which may include the parotid gland. If the parotid gland is involved then it is called parotitis.

Parotitis can be caused by:

  • Infections
    • Viruses – primary mumps but also cytomegalovirus, coxsackievirus and other enteroviruses, lymphocytic choriomeningitis virus, human immunodeficiency virus, influenza A, and parainfluenza virus 1 and 3
    • Mycobacterium, non-tuberculous
    • Staphylococcus aureus
  • Drug reaction – iodides, phenylbutazone, thiouracil
  • Metabolic disorders – diabetes, cirrhosis, malnutrition
  • Pneumoparotitis – i.e. air is forced into the salivary ductal system, e.g. instrument playing, ventilation during anesthesia
  • Psychiatric – bulemia, pica
  • Salivary duct calculi – i.e. sialolithiasis
  • Sjögren’s syndrome
  • Starch ingestion

Mumps belongs to the Paramyxoviridae family of RNA viruses. It is spread by respiratory secretions and humans are the only known natural host. Because of vaccination there are < 300 cases/year in the U.S. with most being in people > 14 years of age. In immunized children, mumps is not a common cause of parotitis.
Incubation is from 16-18 days but cases may occur from 12-25 days after exposure. Maximum communicability is from 1-2 days before parotid swelling to 5 day after onset. About 1/3 of infections do not have clinically apparent salivary gland swelling but only have respiratory symptoms.

Learning Point
The differential diagnosis of a neck mass includes:

  • Infectious lymphadenitis – most common cause of a neck mass. Some agents include:
    • Viral
      • Adenovirus
      • Coxsackie
      • Epstein Barr virus
      • Influenza
      • Parainfluenza
      • Other respiratory viruses
    • Bacterial
      • Staphlococcus aureus
      • Streptococcus, group A beta-hemolytic
      • Bartonella henselae
      • Haemophilus influenzae
      • Anaerobic bacteria if dental infection is suspected
      • Toxoplasmosis – if single lymph nodes
    • Fungal
      • Actinomycosis
      • Histoplasmosis
    • Tuberculous
      • Mycobacterium tuberculi
      • Atypical mycobacterium
    • Unknown
      • Kawasaki disease
  • Noninfectious inflammatory masses
    • Sarcoid
    • Sialadenitis
  • Congenital
    • Branchial anomalies – lie along the anterior border of the sternocleidomastoid muscle or deep to it, occurring anywhere between the external auditory canal and the clavicle.
      There can be cysts, sinuses or fistulas. Remember branchial clefts are external (mainly ectodermal) and branchial pouches are internal (mainly endodermal) in location.

      • First branchial cleft abnormalities – found superior to the hyoid bone
        First cleft and pouch forms ear

      • Second branchial cleft abnormalities – 2/3 of the way down the sternocleidomastoid muscle – most common branchial cleft abnormality
        Second, third, and fourth clefts are obliterated
        Second pouch forms tonsil

      • Third branchial cleft abnormalities – 2/3 of the way down the sternocleidomastoid muscle
        Third pouch forms the parathyroid gland and thymus

      • Fourth branchial cleft abnormalities – are not seen
        Fourth pouch forms parathyroid gland
    • Dermoid cysts
    • Encephalocoeles
    • Laryngocoeles
    • Parathyroid cysts
    • Thyroglossal duct cysts, sinuses and fistulas
    • Thymic cysts
  • Vascular lesions
    • Hemangiomas
    • Hemangiolymphangiomas
    • Lymphangiomas including cystic hygromas
  • Tumor
    • Benign – teratoma, desmoid tumor, myositis ossificans, shortening of the sternocleidomastoid muscle
    • Malignant – histiocytosis, lymphoma, neuroblastoma, schwannomas, rhabdomyosarcoma

Questions for Further Discussion
1. Categorize neck masses by location, i.e. lateral, anterior, posterior?
2. When should lymphadenopathy be evaluated?
3. What types of imaging modalities are available to evaluate neck masses and what are their indications?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Information prescriptions for patients can be found at MedlinePlus for this topic: Neck Injuries and Disorders
and Salivary Gland Disorders.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

Sadler TW, Langman’s Medical Embryology. Williams and Wilkins, Baltimore, MD. 5th edit. 1985;281-294.

American Academy of Pediatrics. Mumps, In Pickering LD, Baker CJ, Long SS, McMillan JA, eds. Red Book: 2006 Report of the Committee on Infectious Diseases. 27th edit. Elk Grove Village, IL: American Academy of Pediatrics; 2006;464-468.

Rudolph CD, et.al. Rudolph’s Pediatrics. 21st edit. McGraw-Hill, New York, NY. 2003:1279-1281.

ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients’ is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

  • Practice Based Learning and Improvement

    13. Information about other populations of patients, especially the larger population from which this patient is drawn, is obtained and used.

    Author
    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa Children’s Hospital

    Date
    October 8, 2007