First case report of thyroid abscess caused by Helicobacter cinaedi presenting with thyroid storm

Helicobacter cinaedi bacterium association with atherosclerosis and other diseases

Helicobacter is a genus of spiral-shaped Gram-negative enterohepatic bacteria whose members are capable of causing bacteremia in humans. One of the poorly studied members of this genus is the bacterium Helicobacter cinaedi. This microorganism was first isolated from human fecal samples in 1984. Although it was long considered to be associated with only immunocompromised patients, more evidence in recent years has implicated H. cinaedi in causing serious pathologies in immunocompetent populations. In addition, H. cinaedi is also reported to be associated with a few chronic or severe illnesses, such as atherosclerosis, which in turn can lead to the development of other cardiovascular pathologies: one of the leading causes of mortality worldwide. Helicobacter cinaedi often goes unnoticed in standard diagnostic methods due to its slow growth under microaerobic conditions. This often leads to significant underdetection and hence undermines the role of this bacterium in the pathogenesis of various diseases and the extent of its spread in humans. In this review, we have compiled information on pathologies associated with H. cinaedi, the occurrence of the bacterium in humans and animals, and the latest developments in diagnosing the bacterium and treating associated diseases.

Thyroid abscess associated with thyrotoxicosis caused by Yersinia enterocolitica subsp. palearctica in a patient with follicular adenoma of the thyroid gland

BACKGROUND

Yersinia enterocolitica is a gram-negative zoonotic bacterial pathogen that is typically transmitted via the fecal-oral route. The most common clinical manifestation of a Y. enterocolitica infection is self-limited gastroenteritis. Although various extraintestinal manifestations of Y. enterocolitica infection have been reported, there are no reports of thyroid abscesses.

CASE PRESENTATION

An 89-year-old Japanese man with follicular adenoma of the left thyroid gland was admitted to our hospital with a 2-day history of fever and left neck pain. Laboratory tests revealed low levels of thyroid stimulating hormone and elevated levels of free thyroxine 4. Contrast-enhanced computed tomography showed low-attenuation areas with peripheral enhancement in the left thyroid gland. He was diagnosed with thyroid abscess and thyrotoxicosis, and treatment with intravenous piperacillin-tazobactam was initiated after collecting blood, drainage fluid, and stool samples. The isolated Gram-negative rod bacteria from blood and drainage fluid cultures was confirmed to be Y. enterocolitica. He was diagnosed with thyroid abscess and thyrotoxicosis due to be Y. enterocolitica subsp. palearctica. The piperacillin-tazobactam was replaced with levofloxacin.

CONCLUSION

We report a novel case of a thyroid abscess associated with thyrotoxicosis caused by Y. enterocolitica subsp. palearctica in a patient with a follicular thyroid adenoma.

Beyond classic concepts in thyroid homeostasis: Immune system and microbiota

It has long been known that thyroid hormones have implications for multiple physiological processes and can lead to serious illness when there is an imbalance in its metabolism. The connections between thyroid hormone metabolism and the immune system have been extensively described, as they can participate in inflammation, autoimmunity, or cancer progression. In addition, changes in the normal intestinal microbiota involve the activation of the immune system while triggering different pathophysiological disorders. Recent studies have linked the microbiota and certain bacterial fragments or metabolites to the regulation of thyroid hormones and the general response in the endocrine system. Even if the biology and function of the thyroid gland has attracted more attention due to its pathophysiological importance, there are essential mechanisms and issues related to it that are related to the interplay between the intestinal microbiota and the immune system and must be further investigated. Here we summarize additional information to uncover these relationships, the knowledge of which would help establish new personalized medical strategies.

Enterohepatic Helicobacter species - clinical importance, host range, and zoonotic potential

The genus Helicobacter defined just over 30 years ago, is a highly diverse and fast-growing group of bacteria that are able to persistently colonize a wide range of animals. The members of this genus are subdivided into two groups with different ecological niches, associated pathologies, and phylogenetic relationships: the gastric Helicobacter (GH) and the enterohepatic Helicobacter (EHH) species. Although GH have been mostly studied, EHH species have become increasingly important as emerging human pathogens and potential zoonotic agents in the last years. This group of bacteria has been associated with the development of several diseases in humans from acute pathologies like gastroenteritis to chronic pathologies that include inflammatory bowel disease, and liver and gallbladder diseases. However, their reservoirs, as well as their routes of transmission, have not been well established yet. Therefore, this review summarizes the current knowledge of taxonomy, epidemiology, and clinical role of the EHH group.

Salmonella thyroid abscess-two case reports

Acute suppurative thyroiditis account for <1% of thyroid diseases and is uncommon because of the gland's encapsulation, iodine-rich environment, good vascular supply and extensive lymphatic drainage. It has been reported in patients with underlying goiters, thyroid cancers and in immuno-compromised patients. The usual causative organisms are Staphylococci spp. and Streptococci spp. Rarer organisms include Klebsiella spp. and Salmonella spp. Due to its rarity (as there have been only 28 cases of Salmonella thyroid abscess being reported in the literature till 2020), only case reports are available to guide management. We report two cases of thyroid abscess due to Salmonella enteritidis in our institution that may herald the re-emergence of this uncommon infection of the thyroid gland and to raise awareness for all clinicians. Both patients presented with neck swelling, dysphagia and sepsis. Surgical intervention was warranted in both patients due to the severity of the disease and failed medical therapy. Recovery was uneventful following adequate surgical intervention and antibiotic therapy according to the culture and sensitivity report of the pathogen. This case report highlights that both patients were immunocompromised, and they contracted Salmonella thyroid abscess without any gastrointestinal involvement. Thus, a high index of suspicion for Salmonella thyroid abscess in immunocompromised patients can expedite the diagnosis and appropriate management can be commenced such as antibiotic therapy, percutaneous aspiration and surgical drainage in the event of failed medical therapy.

THYROID ABSCESS AFTER INJECTION OF HEROIN INTO THE NECK COMPLICATED BY THYROID STORM

Objective

Our objective is to present a case of thyroid abscess complicated by thyroid storm secondary to intravenous drug use. Cases of thyroid abscess causing thyrotoxicosis are rare. This is the first report of thyroid abscess from intrathyroidal injection of illicit drugs resulting in thyroid storm.

Methods

We used biochemical evaluation, computed tomography (CT), and ultrasound to assess the thyroid abscess. Treatment included antithyroid drugs, steroids, antibiotics, and surgical drainage.

Results

A 28-year-old female presented with neck pain and fever after injecting heroin into her neck. CT showed bilateral thyroid abscesses measuring 3.0 cm on the left and 2.0 cm on the right. Thyroid-stimulating hormone (TSH) was 0.40 mIU/L (reference range is 0.34 to 5.60 mIU/L). She left against medical advice, then returned with worsening symptoms. CT showed multiloculated, bilateral thyroid abscess measuring 8.6 cm on the left and 5.3 cm on the right. She suffered a cardiac arrest and was resuscitated. Her white blood cell count was 25.9 × 10³ cells/mL, TSH <0.01 mIU/L, free thyroxine was 4.25 ng/dL (reference range is 0.89 to 1.76 ng/dL), triiodothyronine was 96 ng/dL (reference range is 70 to 204 ng/dL), and thyroid-stimulating immunoglobulin was <89% (reference range is <140%). She had fever, tachycardia, heart failure, and elevated bilirubin confirming a diagnosis of thyroid storm by Japan Thyroid Association criteria and Burch-Wartofsky score. She was treated with propylthiouracil, hydrocortisone, and antibiotics. Two days later her TSH was <0.005 mIU/L, free thyroxine was 3.06 ng/dL, and triiodothyronine was 62.0 ng/dL. Ultrasound showed enlarged, heterogeneous thyroid with loculated fluid collections. Following surgical abscess drainage, her thyroid function normalized and progressed to hypothyroidism.

Conclusion

We conclude that thyroid abscess can be a life-threatening complication of intravenous drug use as it can precipitate thyroid storm. Along with surgical drainage of the abscess, successful management includes antithyroid drugs, antibiotics, and steroids to control thyrotoxicosis, infection, and inflammation.

Review: Other Helicobacter species

This article is a review of the most important, accessible, and relevant literature published between April 2018 and April 2019 in the field of Helicobacter species other than Helicobacter pylori. The initial part of the review covers new insights regarding the presence of gastric and enterohepatic non-H. pylori Helicobacter species (NHPH) in humans and animals, while the subsequent section focuses on the progress in our understanding of the pathogenicity and evolution of these species. Over the last year, relatively few cases of gastric NHPH infections in humans were published, with most NHPH infections being attributed to enterohepatic Helicobacters. A novel species, designated "Helicobacter caesarodunensis," was isolated from the blood of a febrile patient and numerous cases of human Helicobacter cinaedi infections underlined this species as a true emerging pathogen. With regard to NHPH in animals, canine/feline gastric NHPH cause little or no harm in their natural host; however they can become opportunistic when translocated to the hepatobiliary tract. The role of enterohepatic Helicobacter species in colorectal tumors in pets has also been highlighted. Several studies in rodent models have further elucidated the mechanisms underlying the development of NHPH-related disease, and the extra-gastric effects of a Helicobacter suis infection on brain homeostasis was also studied. Comparative genomics facilitated a breakthrough in the evolutionary history of Helicobacter in general and NHPH in particular. Investigation of the genome of Helicobacter apodemus revealed particular traits with regard to its virulence factors. A range of compounds including mulberries, dietary fiber, ginseng, and avian eggs which target the gut microbiota have also been shown to affect Helicobacter growth, with a potential therapeutic utilization and increase in survival.