A 38-year-old man has advanced AIDS. About a year ago, he presented with signs of HIV dementia and wasting syndrome, and his CD4 count was <50. He has been routinely evaluated since the initial diagnosis. Eosinophilic folliculitis and Candida stomatitits are his only documented opportunistic infections. His regular medications include AZT (zidovudine), D4T (stavudine), indinavir (protease inhibitor), itraconazole (folliculitis treatment, Candida prophylaxis), acyclovir (HSV prophylaxis), monthly pentamidine (for Pneumocystis carinii (jirovecii) prophylaxis), marinol (treatment of HIV wasting), and pepcid (for peptic ulcer disease).

Two months ago, the patient underwent a tooth extraction (an infected mandibular molar), seemingly without incident. Two weeks ago, he experienced a sore throat, sinus congestion, and cough. He was seen at his usual clinic and treated with a 10-day course of Cefuroxime, after which his symptoms improved. However, two days ago, he returned to the clinic complaining of neck stiffness, headache, sore throat, and decreased appetite. He was tested for meningitis, but the results were negative and he was discharged home. His CD4 count was 200, with HIV-1 RNA level of <50 copies/mL.

Now the patient has returned again, complaining of a worsening sore throat, odynophagia, trouble swallowing his oral secretions, difficulty in breathing, decreased appetite, and a noticeable fever that has persisted for the past two days. On examination, the man is in significant distress, sitting upright, drooling, with some use of accessory muscles of respiration. The man can only give garbled, one-word answers to questions because of swelling and upward/posterior displacement of his tongue. Vital signs are T = 39 C, R = 100, P = 24, BP = 130/80 mm Hg. Tender, bilateral submandibular swelling (greater on the right than on the left) is evident. Fluctuance is insignificant. Sublingual swelling is indicated by upward displacement of the tongue. No cervical, supraclavicular, infraclavicular, pre/posterior auricular, or axillary lymphadenopathy is detected. Examination of the oropharynx is hindered by marked trismus of 25 mm. The right tonsil has a yellow-white exudate and is erythematous, but the left tonsil is clear. A large area (3 x 3 cm) of the right soft palate is swollen.

The patient is now evaluated by the Otolaryngology team because of the potential for rapid compromise of his airway and the need for better visualization of the pharynx. The team members note normal vocal cords, a fully patent airway, right arytenoid fold swelling, and slight fullness of the right pharyngeal wall. There are no signs of supraglottitis or epiglottitis. A CT scan of the neck and sinuses indicates significant bilateral peripharyngeal, retropharyngeal, and paravertebral space soft tissue inflammatory change with edema. Right sided spaces are more involved than left. Swelling distorts and compresses the oropharynx. The left common and external jugular veins are thrombosed. Finally, there is evidence of chronic sinusitis.

Question 4.1: What is your preliminary diagnosis?

Some type of deep neck infection or abscess is indicated. The specific symptoms seen here are suggestive of Ludwig's angina, a potentially life-threatening cellulitis of the floor of the mouth, with infection extending into the sublingual, submental, and submaxillary spaces. "Angina" is derived from the Latin word "angere" which means to strangle. Ludwig's angina appropriately describes the subset of deep neck abscesses in which swelling of critical spaces threatens to elevate the floor of the mouth and displace the tongue posteriorly, and, thereby, strangle the patient. Four criteria have been proposed to distinguish Ludwig's angina from other forms of deep neck abscesses. The infection must (1) occur bilaterally, in more than one space; (2) produce gangrenous serosanguinous infiltration with or without pus; (3) involve connective tissues, muscle and fascia, but not glandular structures; and (4) spread by continuity rather than by lymphatics.

Question 4.2: How did this infection start and develop?

It is likely that this infection is related to the patient's prior tooth extraction. Dental procedures and poor oral hygiene account for 70-90% of Ludwig's angina cases. Dental procedures involving the second and third molars are common sources of infection. The roots of these molars extend into the mylohyoid muscle, thus supplying a route to the three primary mandibular spaces. The infection typically begins in the necrotic pulp of a tooth and then invades the adjacent bony tissue. After a period of spread within the bony tissue, the infection may erode the thinnest part of the bony cortex and, thereby, gain access to muscle and soft tissue. If erosion happens above the muscle attachment site, the fascial space is entered. Because the submandibular and sublingual spaces freely communicate, the infection can spread rapidly (and with grave consequences) after the deep cervical fascia is involved.

Question 4.3: Were there any predisposing factors?

The patient is in the advanced stage of AIDS. Systemic illnesses, trauma, and intravenous drug abuse are common precursors to Ludwig's angina cases that occur today. One recent review reporting the incidence of various illnesses associated with Ludwig's angina discovered that 18% of cases involves diabetes mellitus, 9% AIDS, and another 5% HIV-positive patients.

Question 4.4: What are causative agents?

Deep neck abscesses generally involve members of the normal mouth flora. Obligate anaerobes constitute (75% of the normal oral flora and account for (40% of Ludwig's angina cases. The most important pathogens are anaerobic streptococci, Porphyromonas spp., and Prevotella spp. Most deep neck abscesses are polymicrobial and might include anaerobes and aerobes. Among the most frequently seen aerobes are Staphylococcus aureus and Staphylococcus epidermidis.

Question 4.5: How is this disease treated?

There are four principal components to treatment of Ludwig's angina. (1) Airway management is essential. 67% of patients with Ludwig's angina require either anticipatory or emergent intubation. (2) Antibiotic therapy must be designed to cover both anaerobes and S. aureus. Penicillin with or without metronidazole is the first-line therapy. Clindamycin, metronidazole alone, or amoxicillin/clavulinic acid are also considered highly effective. Treatment (intravenous therapy followed by oral therapy) must be continued for at least 14 days. Empiric treatment in an immunocompetent host is considered safe; however, medical therapy must be guided by cultures and sensitivities in immunocompromised patients. (3) Inclusion and drainage of abscesses was routine in the past. Now, surgical therapy is usually reserved for cases that do not respond quickly to medical treatment. (4) Adequate nutrition and hydration are important and can be something of a challenge in patients with significant oropharyngeal edema.