Case report: Group a streptococcus toxic shock syndrome post hemithyroidectomy : Report of a case and literature review of presenting symptoms

LEARNING OBJECTIVE #1: Disseminated Group A Streptococcus (GAS) infection and streptococcal toxic shock syndrome following thyroidectomy has previously been described but remains a rare consequence of the surgery. We describe a case and review literature on presenting symptoms and modes of transmission. CASE: Our patient was a 45 year-old woman admitted in October 2013 for an elective hemi-thyroidectomy for a nodule with pathology suspicious for papillary thyroid carcinoma. Her past medical history was pertinent for thalassemia minor and a remote provoked deep vein thrombosis (DVT). The day of surgery, the patient had reported mild upper respiratory tract symptoms. The surgery progressed in an uneventful fashion. No antibiotics were administered perioperatively. Twelve hours post-operatively, while hospitalised, the patient developed severe emesis, diarrhea, tachypnea and significant musculoskeletal pain. At the time, the patient was afebrile with normal laboratory investigations. During the next six hours, the patient became hypotensive and developed a lactic acidosis despite aggressive fluid resuscitation. The neck wound did not appear infected. Piperacillin tazobactam intravenously (IV), vancomycin per os (incidence of Clostridium difficile colitis being common in our institution) and oseltamivir IV were started. She required intubation and vasopressor support with maximal doses of norepinephrine, epinephrine and vasopressin. Continuous renal replacement therapy was initiated for anuric acute renal failure. An echocardiogram showed a globally depressed left ventricular ejection fraction of 30 % and abdominal computed tomography demonstrated pancolitis and the presence of an intrauterine device. Despite all efforts, the patient continued to require maximal support. Initial gram stain showed gram positive cocci in pairs and chains. Forty-eight hours later, blood cultures grew group A streptococcus (Streptococcus pyogenes). The serotype was serotype A, T12, emm12, Factor OF +. Her initial antibiotics were discontinued and she was started on Penicillin G IV, clindamycin IV, ceftriaxone IV and vancomycin IV as per protocol in our institution. Furthermore, a daily dose of intravenous immunoglobulin over 3 days was administered. Endotracheal aspirate grew GAS. Apelvic examination showed no purulent discharge, but a swab was positive for GAS. Her intrauterine device was removed. Further imaging and drainage demonstrated the presence of a large purulent right pleural effusion which failed to grow GAS (Image 1). She was extubated on day 10 and had a favorable course thereafter. DISCUSSION: Post-surgical GAS is defined as invasive GAS infection that occurs during the first 7 days following surgery(1). Thyroidectomies are rarely complicated by infection, but invasive GAS has been described as a possible complication of the procedure. An extensive literature revealed 21 cases of severe GAS infections postthyroid surgery through PubMed and Medline from 1996 to March 2014, in the form of case reports or audits. Of these 21 reported cases, at least 10 were associated with STSS. The case fatality rate of post thyroidectomy GAS is almost 50 % (10 out of 21) based on the reported cases identified. GAS infection post thyroidectomy presented within 24-48 h following surgery and, in many cases, has a fulminant course, requiring ICU admission for hemodynamic support of multi-organ dysfunction. The mode of acquisition appears variable: patient carrier, family member, surgeon or unknown (2-9). Of the cases where details about the clinical course was available (total of 20 cases), 17 reported evidence of a wound infection suggestive of a portal of entry for GAS during the operation. In only 3 cases was the wound intact with no need for exploration or debridement, similar to our case (2, 4, 7). In these three reported cases, the first presented with streptococcal pneumonia; the second with vomiting, hypotension, tachypnea and anuria and the third with fever, thoracic pain and tachycardia. In all three cases the symptoms began within 24-48 h of the thyroid surgery and in each case, the patient was admitted to the intensive care for septic shock and hemodynamic support. One of the three patients died(4). It can be hypothesised that direct transmission/translocation of bacteria from the throat into the bronchopulmonary tree during intubation was a possible mechanism of spread in our patient's case, as well as the three other similar cases. In our case, the patient was colonised with GAS. Secondary transmission from a member of the operating team is unlikely since there was no evidence of fasciitis or surgical wound infection. As in our patient, the emm12 serotype of GAS has been reported in other STSS cases (10). In view of our patient having a prior history of GAS pharyngitis treated with antibiotics, it is strongly suspected that endotracheal manipulation during intubation in the setting of GAS colonization resulted in bacterial translocation and invasive STSS.