1st known case of IJV thrombosis linked to oral germ G. adiacens

The oral bacterium Granulicatella adiacens led to internal jugular vein (IJV) thrombosis in a man with poor oral hygiene and periodontitis, in a case published on January 20 in BMJ Case Reports.

This is believed to be the first reported case of IJV thrombosis associated with G. adiacens, according to the authors.

"When confronted with G. adiacens [bacteremia] in patients with poor oral hygiene, it is necessary to be cautious of the fact that this organism can cause IJV thrombophlebitis," wrote the group, led by Dr. Honami Kawai of the department of general internal medicine at Kokuho Asahi Chuo Hospital in Chiba, Japan.

IJV thrombophlebitis is usually caused by normal oropharyngeal flora, with the bacterium Fusobacterium necrophorum being the most common. When F. necrophorum causes thrombophlebitis, it is referred to as Lemierre syndrome or "forgotten disease."

The condition often originates from head and neck infections, as well as primary dental infections. G. adiacens is a variant streptococcus that is naturally found in dental plaque and can cause endodontic infections and dental abscesses.

A 58-year-old man

The patient, who was being treated with lithium for bipolar disorder, was transferred to the hospital after he was found unconscious on the floor of his home. He had no other medical conditions, no prostheses, and no history of recent dental procedures or intra-articular injections. The patient looked sick and had a fever.

A dental exam revealed the man had poor oral hygiene and periodontitis, but there were no signs of pharyngitis or tonsillitis, and no swelling or erythema was detected on his neck. Initial blood tests revealed increased inflammatory markers with a C-reactive protein level of 2.42 mg/dL, leukocytosis with a white blood cell count of 21,500/µL, and a platelet count of 26.4 × 10⁴/µL. He showed impaired renal function with a urea level of 60 mg/dL, a creatinine level of 2.21 mg/dL, and an elevated lithium level of 2.08 mEq/L.

After he was diagnosed with lithium intoxication, he underwent hemodialysis. Because clinicians thought he may have septic encephalopathy, blood samples had been taken. The results showed he was positive for Gram-positive cocci chains after 20 hours of incubation, and they were identified as G. adiacens on day 3, the authors wrote.

To identify the origin of the infection, a pan-scan computed tomography (CT) exam with contrast was performed. It revealed left cervical vein thrombosis, multiple intramuscular gluteal abscesses around the trochanteric region of the left femur, and a pulmonary embolism. He had no abscesses and no other focal infection sites in his oral cavity, and a transthoracic echocardiogram showed no vegetation or valvular dysfunction, according to the authors.

Diagnosis and treatment

The clinicians determined that a G. adiacens infection in the mouth had spread to the IJV, causing septic metastases in the lung and gluteal muscles. They decided to treat him with long-term antibiotics until the abscesses and thrombophlebitis were resolved.

A CT scan performed on day 40 showed that the pulmonary embolism was gone, but the left cervical vein thrombus had not diminished in size, and abscesses around his left femur had become larger. This required incision and drainage. After drainage, edoxaban therapy was started.

A CT scan taken on day 56 showed that the left cervical vein thrombus and gluteal abscesses had resolved. Nevertheless, at day 90, magnetic resonance imaging (MRI) showed areas of restricted drug diffusion around the trochanteric region of the left femur. Radiologists and microbiologists prescribed continuation of antibiotics due to the gluteal abscesses not being completely gone, the authors noted.

On his 98th day at the hospital, the man was discharged. He was prescribed amoxicillin for another two weeks and long-term administration of edoxaban. Also, the patient was sent to another hospital for extended psychiatric care.

The case indicates that clinicians need to know that oral bacteria can cause a host of medical conditions, the authors wrote.

"In cases of [bacteremia] caused by oral microflora, we need to be aware of the fact that these organisms can cause IJV thrombophlebitis with complications of multiple metastases to other organs," they added.