In total six patients with thyroid abscess was included (five females). The abscesses were equally commonly located in each thyroid lobe. Median age at presentation was 51 years (28-73 years). None had third or fourth left branchial cleft anomalies nor was immunosuppressed. All patients were successfully treated with antibiotics for 13.5 days (10-41 days), drainage in three, and surgery was performed twice in the acute phase in one and at a later state in one. The length of hospital stay was 7.5 days (4-79 days). Median follow-up time was 7 years (3-12 years). A detailed description is given in the case presentations below and the clinical data are summarized in Table 1.
Case 1
A 48-year-old woman with hypertension and goitre presented with three weeks of on and off fever together with symptoms from the urinary tract and gut. She presented to the Emergency Department with a fever of 40◦C, cough, tachycardia and pain located to the left ear and to the anterior neck. The goitre was tender and to some extent hard but not fluctuating at palpation. From the left lung crepitations were heard on auscultation. The blood biochemical investigations revealed: ESR 28 mm (normal <20), CRP 180 mg/L (<3), alanine aminotransferase 2.25 µkat/L (<0.76), aspartate aminotransferase 1.31 µkat/L (<0.61), potassium 3.3 mmol/L (3.6-4.6), TSH 0.1 mIU/L (0.4-4.7), free T4 15 pmol/L (12-23) and free T3 3.9 pmol/L (3.0-6.5). No TRAb or TPOab were detected, and other blood tests were normal as were a chest X-ray. She received treatment with prednisolone 30 mg due to suspicion of a subacute thyroiditis, was discharged due to social reasons, and were planned to return the following day. As fever persisted the next day she was admitted, blood cultures were drawn and a FNA from the thyroid performed. Prednisolone was continued with addition of iv cloxacillin 2g tds and iv benzylpenicillin 3g tds. Cytology showed granulocytes and a few lymphocytes together with macrophages, colloid and blood. Blood cultures were positive for streptococcus pneumonia, and cloxacillin and prednisolone were withheld. After six days with improvements, CRP had decreased to 80 mg/L, iv benzylpenicillin was changed to per oral phenoxymethylpenicillin 2g tds for an additional week. The dental status was normal. The conclusion was sepsis with acute thyroiditis and she was discharged after 12 days. Three weeks later she was well but had a foul taste in mouth. MRI was performed but this could not reveal any fistula or branchial arch anomalies. There had been no recurrence at last follow-up 11 years later.
Case 2
A 54-year-old male with a previous nephrectomy due to a renal cell carcinoma, and benign prostate hyperplasia was seen regularly by the General Practitioner. He had also had multiple prostate biopsies to exclude malignancy. After such a biopsy, he was treated for a urinary septicaemia. A month after that he got flu like symptoms, exhaustion and headache. Seven weeks after the biopsy he presented to the Emergency Department with fever, sweating, loss of appetite, pain in the throat and a foul metal taste. Examination revealed an enlargement of the right thyroid lobe, palpable lymph glands along the sternocleidomastoid muscle, a tachycardia of 119 beats per minutes and a CRP of 328 mg/L (<3). He was admitted with a suspected infection or malignancy. CT showed a suspect thyroid abscess in the level of the jugulum with suspicion of mediastinitis. He was treated initially with oral ceftibuten 400mg once daily which was changed to iv imipenem/cilastatin 1g tds and iv clindamycin 600mg qid for five days. An echocardiogram to exclude endocarditis was performed which was normal. At an ultrasound guided puncture of the thyroid, brownish pus was seen, and a thyroid drain was inserted. TSH was 0.08 mIU/L (0.4-3.5) and free T4 57 pmol/L (8-14), and po propranolol 20 mg tds was initiated. TRAb and TPOab were negative. Clinical improvement was noted with a decrease in CRP but also an accentuation of hyperthyroidism after five days, which then gradually subsided. Antibiotics were switched to oral ceftibuten 400mg od for another two weeks. Blood cultures were negative, as were cultures of mycobacterium, urine, throat and nasopharynx, but deep culture from the thyroid showed two variants of escherichia coli. He lost 8 kg and was hospitalized for seven days but at follow-up had regained weight and thyroid parameters were normalized. He was later lost to follow-up but had not been referred again during the last 10 years and was still alive.
Case 3
A 73-year-old woman presented to the Emergency Department because of a swollen and tender resistance in the neck for five days, and fever of 38°C the last two days. She had difficulties to swallow. Two years earlier she had had the same experience, FNA at that time was normal and the swollenness subsided spontaneously. Epipharynx, hypopharynx and larynx were normal at inspection. CRP was 104 mg/L (<3), ESR 40 mm (<30) and thyroid function tests were normal. The left part of the thyroid was enlarged, tender and an erythema 10-15 cm in diameter was seen in the anterior neck. Ultrasound revealed a 30x30x30 mm mass in the thyroid with low echogenicity, and a deep puncture for culture and drainage was performed and brownish fluid was extracted. She was treated with oral clindamycin 300mg tds and oral ciprofloxacin 500mg bid. The following day she continued to have high fever (38.6°C). Thyroid surgery was considered. Due to a tick bite a week prior borrelia infection was excluded. Fever, local symptoms and laboratory subsided, she was admitted for four days and antibiotics were continued for in total 10 days. All cultures were negative. A FNA two weeks after discharge showed a colloid cyst, and she had no longer difficulties to swallow. She is still euthyroid without medication four years after this episode.
Case 4
A 44-year-old woman had a FNA done because of a lump in the right side of the thyroid. Brownish fluid was evacuated, and the lump diminished. Thyroid function tests were normal. Two weeks later the lump increased in size and she presented to Emergency Department. She complained of pain during swallowing, difficulty in eating and experienced dyspnoea when lying down. Fever was fluctuating up to 39°C. In the right side of the thyroid a 2x4 cm hard and tender lump was palpated. CRP was 87 mg/L (<3), ESR 26 mm (<20) and leukocytes 12.9x10(9)/L (3.5-8.8). A new FNA with deep culture was done from the thyroid and 10 mL brownish fluid was drained. Iv cefuroxime 1.5 g tds was commenced. CT neck showed a 30x27x34 mm mass in the right thyroid lobe. Cultures from blood and thyroid tissue were all negative. After three days, local symptoms had much improved, CRP was 42 mg/L and ESR 29 mm. Antibiotics were changed to po sulfamethoxazole/trimethoprim 800/160 mg bid for another week, and all symptoms subsided. The length of admission was four days. Six month later she represented to Emergency Department with symptoms from the thyroid gland, but the thyroid ultrasound only showed a 14x8 mm cyst. She continued to be euthyroid and well four years after the first presentation.
Case 5
A 68-year old woman came to the Emergency Department at a county hospital with dyspnea, atrial flutter, fever (38.4°C) and a CRP of 426 mg/L (<4). CT thorax displayed infiltrates in the left lung and signs of heart failure. She developed sepsis and was admitted to the intensive care unit where she was intubated, and later the same day transferred to a tertiary hospital. By that time treatment with iv piperacillin/tazobactam 4g/0.5g tds and a single dose of iv garamycin 460mg had been commenced. Serum calcium was 3.70 mmol/L (2.10-2.55) and parathyroid hormone level (PTH) 594 ng/L (10-73). Antibiotic treatment was continued, and she required noradrenaline to compensate low blood pressure, in addition to amiodarone infusion for atrial flutter. One episode with ventricular fibrillation was cured with cardioversion. Due to continuing respiratory distress tracheotomy was performed after 11 day. From the left thyroid lobe and parotic gland large amounts of pus was drained, with less extent of pus from the lower part of the left lobe. The left thyroid lobe was highly fibrotic in a para pharyngeal abscess. Isthmectomy was performed, but anatomic structures were not identifiable. Cultures from nasopharynx showed airway pathogens, from pus candida, from blood streptococci sanguineous, from pleura coagulase negative staphylococci and later from faeces clostridium difficile. She also had a bilateral pleura empyema which was drained repeatedly. Piperacillin/tazobactam was changed after a week to iv imipenem/cilastatin for three weeks together with iv metronidazole, and later iv vancomycin. The thyroid abscess was drained once again after a week. She was treated at the intensive care unit for 37 days in total and thereafter transferred to a medical ward for another six weeks. PTH continued to rise to 1368 ng/L, whereas serum calcium was maintained normal with cinacalcet 60 mg od. Parathyroid scintigraphy was positive on the left side, which was operated five months later, after she had had an extensive treatment at a Rehabilitation Center. The removed parathyroid gland weighed 0.7 g and was judged by the pathologist as a parathyroid adenoma. The calcium levels normalized, but PTH elevation persisted the following years between 175 to 565 ng/L. CT thorax and neck after parathyroidectomy did not display any remaining abscess, pleural thickening, enlarged lymph glands or parathyroid adenoma. She passed away three years later in asystole, secondary to severe heart failure and pneumonia.
Case 6
A previously healthy 28-year old woman had three months after delivery developed left-sided swollenness in the neck, pain, fever and tachycardia in the last 10 days. At another hospital this was suspected as a subacute thyroiditis as TSH was 0.1 mIU/L (0.4-3.5) and free T4 21 pmol/L (10-22). Thyroglobulin was normal. Treatment was commenced with oral prednisolone 25mg daily and she was discharged after two days. One day later she returned with progression of the lump in the neck and breathing difficulties. She was admitted to the intensive care unit at the tertiary hospital with the combined diagnosis of epiglottitis and acute thyroiditis. At this time there was a non-tender 50x50 mm large lump to the side of the throat with no erythema. Heart frequency was 132 beats per minute and temperature 39.3°C. Increasing edema of the glottis was noted and she could not swallow but had no stridor. Iv cefuroxime 1.5g tds was initiated. Repeated fiberscope examinations showed progressive edema and she was subsequently intubated. A CT showed a 70 mm large multicystic process in the left thyroid lobe expanding cranially and dorsally dislocating the larynx to the right, as a thyroid abscess, which was drained with three drains. There was an anaerobe smell from the extracted pus, and iv 1000mg metronidazole od added for four days. Clinically she improved and could leave the intensive care unit after five days, and the hospital after additional three days. Cultures from nasopharynx revealed hemophilic influenza, and from blood pepto streptococci. In the abscess there was also hemophilic influenza. Iv antibiotic treatment was altered to oral metronidazole 400mg tds for five days and amoxicillin/clavulanic acid 875/125 mg bid for ten days. Thyroid function tests were normalized after one months. There has been no recurrence at the review eight years later.