Tigecycline-Associated Hepatic Steatosis After Liver Transplant: A Case Report.

Tigecycline is a parenteral glycycline antibiotic that is used to treat severe infections caused by susceptible organisms, butitis also associated with hepatotoxicity. We present 2 similar patients with hepatic steatosis possibly associated with early tigecycline after transplant. In the first case, a 61-year-old woman underwent liver transplant for acute severe hepatitis; 6 days posttransplant, because of nonroutine resistant fever, the patient received tigecycline combined with daptomycin. Retransplant was applied to the patient on day 12 posttransplant because of acute liver failure secondary to hepatic vein thrombosis. After retransplant, biochemical levels gradually increased, exceeding the upper limit of normal. In liver biopsy, the patient had macrovesicular steatosis in 70% to 80% ofthe parenchyma. In the second case, a 53-yearold woman underwent liver transplant for liver cirrhosis. Tigecycline was added to the treatment because of recurrent fever on day 6 after transplant, with treatment also comprising piperacillin-tazobactam and meropenem. On day 15 of the patient's tigecycline treatment, her liver function tests were elevated. In liver biopsy, the patient had 30% to 40% macrovesicular steatosis and canalicular cholestasis in the parenchyma, especially in zone 3. Reports of hepatic steatosis associated with early tigecycline after transplant are quite new to the literature.

Tigecycline-associated hypofibrinogenemia: A single center, retrospective, controlled study.

BACKGROUND: Tigecycline-associated hypofibrinogenemia has been reported as an important adverse effect in recent years, but controlled studies minimizing confounding factors are needed. The objective of our study was to assess changes in fibrinogen levels in patients for hospitalization, comparing two antibiotic episodes (tigecycline and other) within the same patients. METHODS: The retrospective, self-controlled case series study was conducted at our University Hospitals. The study compared the change in fibrinogen levels during the patient's hospitalization for tigecycline (TigePer) and another antibiotic period (OtherPer). In addition, bleeding events, bleeding risk (determined by the IMPROVE bleeding risk score), as well as 15- and 30-day mortality rates between TigePer and OtherPer were compared. RESULTS: The study enrolled 50 patients with 100 episodes of antibiotic treatment. The median age (interquartile range) of the patients was 68.5 (21.5) years, and 38 % were female. As compared to OtherPer, TigePer had a statistically significant reduction in fibrinogen levels (p < 0.001), with a hypofibrinogenemia rate of 40 % in TigePer as compared to 2 % in OtherPer (p < 0.001). TigePer demonstrated a significantly higher 15-day mortality rate (p = 0.006). No significant differences were observed between the two periods in terms of bleeding risk, rate of bleeding events, and 30-day mortality rate (p > 0.05). CONCLUSION: Hypofibrinogenemia and other coagulopathies, without associated bleeding events, are more frequently observed in patients receiving tigecycline. Therefore, it is crucial for clinicians to monitor fibrinogen levels during tigecycline use.

Safety of Tigecycline in Patients on Antithrombotic Therapy: A Single-Center Retrospective Study.

INTRODUCTION: The aims of the study were to investigate the risk factors of tigecycline-induced hypofibrinogenemia and to evaluate the safety of tigecycline with concomitant antithrombotic drugs. METHODS: We performed a retrospective analysis of patients who received tigecycline for more than 3 days between January 2015 and June 2019. Clinical and laboratory data were collected including fibrinogen concertation, tigecycline dose, duration of treatment, disease severity, complete blood count, indicators of infection, liver and renal function. Risk factors of hypofibrinogenemia were analyzed by univariate and multivariate analysis. To evaluate the safety of tigecycline and concomitant antithrombotic drugs, bleeding events were assessed by comparing the decline in hemoglobin and the amount of red blood cell transfusion in patients with antithrombotic drugs and those without. RESULTS: This study included a total of 68 cases, 20 of which experienced hypofibrinogenemia while receiving tigecycline treatment. Duration of treatment, cefoperazone/sulbactam combination therapy, and fibrinogen levels prior to initiation of tigecycline were risk factors associated with tigecycline-induced hypofibrinogenemia. There were 26 recorded bleeding incidents, 25 of which happened before the start of tigecycline. Antithrombotic and non-antithrombotic patients did not differ in their hemoglobin decline or need for red blood cell transfusions while taking tigecycline. CONCLUSION: A longer treatment duration, cefoperazone/sulbactam combination therapy, and a lower level of fibrinogen before tigecycline were associated with an increased risk of tigecycline-induced hypofibrinogenemia. A combination of antithrombotic drugs and tigecycline did not aggravate the bleeding events during tigecycline treatment.

Acute pancreatitis caused by tigecycline and furosemide combination treatment and hypofibrinogenemia caused by tigecycline: A case report.

OBJECTIVE: We describe a case of acute pancreatitis (AP) and hypofibrinogenemia associated with drug treatment with the aim to increase awareness of uncommon yet possibly life-threatening adverse reactions of tigecycline and furosemide. CASE SUMMARY: A 75-year-old Chinese male was hospitalized for acute non-ST-elevation myocardial infarction and acute heart failure. The patient underwent successful percutaneous coronary intervention and MitraClip. Furosemide was taken since admission. Because Acinetobacter baumannii was detected in the blood and sputum, the patient was treated with tigecycline from the 14th day of hospitalization. Abnormal pancreatitis parameters were observed, and pancreatic CT was undertaken 12 days after the treatment of tigecycline. AP was diagnosed and symptomatic treatment was carried out, but no significant improvement was observed. On the 33rd day of hospitalization, the patient presented with acute upper gastrointestinal bleeding and decreased levels of fibrinogen and platelets. After withdrawal of tigecycline, the coagulation and pancreatitis parameters improved significantly. However, the pancreatitis parameters increased again after stopping somatostatin. Therefore, somatostatin was given again for 1 day, and furosemide was discontinued. After that, the pancreatitis parameters returned to baseline levels after a slight recovery. CONCLUSION: Clinicians should pay attention to clinical signs, symptoms, and pancreatic enzymes during tigecycline or furosemide treatment, especially when used in combination. In addition, regular monitoring of fibrinogen and platelet count during tigecycline treatment is suggested.

Clinical characteristics and risk factors for tigecycline-induced pancreatitis in a tertiary hospital: A retrospective study.

AIMS: To analyse the clinical characteristics and risk factors for tigecycline-induced pancreatitis (TIP) and evaluate the safety and efficiency of tigecycline use in non-TIP. METHODS: A retrospective case-control study was conducted on adult and juvenile patients administered tigecycline for >3 days. The adults were classified as TIP, non-TIP (pancreatitis with other causes) and non-pancreatitis. Univariate analyses were performed to compare TIP and non-pancreatitis, and multivariate analysis was used to identify risk factors for TIP. The clinical characteristics of TIP, and the safety and efficiency of tigecycline use in non-TIP were evaluated. RESULTS: A total of 3910 patients (3823 adults and 87 juveniles) were enrolled. The adult patients comprised 21 TIP, 82 non-TIP and 3720 non-pancreatitis. The TIP prevalence was 0.56% in adults and 1.15% in juveniles. The mean time from tigecycline use to symptom onset was 7.2 days, and all cases were mild pancreatitis. The mean time from tigecycline withdrawal to symptom relief was 3.6 days. The multivariate analysis identified comorbid renal insufficiency as an independent risk factor for TIP (odds ratio = 3.032). Among the 82 non-TIP patients, 81.7% had severe pancreatitis and 47.6% had necrotizing pancreatitis. The modified computed tomography severity score after tigecycline use was similar to that before tigecycline use, but the pancreatic enzymes and infection indices were significantly decreased. CONCLUSIONS: The prevalence of TIP was low. Comorbid renal insufficiency was as an independent risk factor for TIP. Tigecycline is safe and efficient for treatment of pancreatitis, especially necrotizing pancreatitis, with intra-abdominal infection.

Tigecycline reduces tumorigenesis in colorectal cancer via inhibition of cell proliferation and modulation of immune response.

BACKGROUND: and Purpose: Colorectal cancer (CRC) is one of the cancers with the highest incidence in which APC gene mutations occur in almost 80% of patients. This mutation leads to ß-catenin aberrant accumulation and an uncontrolled proliferation. Apoptosis evasion, changes in the immune response and microbiota composition are also events that arise in CRC. Tetracyclines are drugs with proven antibiotic and immunomodulatory properties that have shown cytotoxic activity against different tumor cell lines. EXPERIMENTAL APPROACH: The effect of tigecycline was evaluated in vitro in HCT116 cells and in vivo in a colitis-associated colorectal cancer (CAC) murine model. 5-fluorouracil was assayed as positive control in both studies. KEY RESULTS: Tigecycline showed an antiproliferative activity targeting the Wnt/ß-catenin pathway and downregulating STAT3. Moreover, tigecycline induced apoptosis through extrinsic, intrinsic and endoplasmic reticulum pathways converging on an increase of CASP7 levels. Furthermore, tigecycline modulated the immune response in CAC, reducing the cancer-associated inflammation through downregulation of cytokines expression. Additionally, tigecycline favored the cytotoxic activity of cytotoxic T lymphocytes (CTLs), one of the main immune defenses against tumor cells. Lastly, the antibiotic reestablished the gut dysbiosis in CAC mice increasing the abundance of bacterial genera and species, such as Akkermansia and Parabacteroides distasonis, that act as protectors against tumor development. These findings resulted in a reduction of the number of tumors and an amelioration of the tumorigenesis process in CAC. CONCLUSION AND IMPLICATIONS: Tigecycline exerts a beneficial effect against CRC supporting the use of this antibiotic for the treatment of this disease.

Sustained activation of EGFR-ERK1/2 signaling limits the response to tigecycline-induced mitochondrial respiratory deficiency in liver cancer.

BACKGROUND: Identification of tumor dependencies is important for developing therapeutic strategies for liver cancer. METHODS: A genome-wide CRISPR screen was performed for finding critical vulnerabilities in liver cancer cells. Compounds screen, RNA sequencing, and human phospho-receptor tyrosine kinase arrays were applied to explore mechanisms and search for synergistic drugs. FINDINGS: We identified mitochondrial translation-related genes associated with proliferation for liver cancer cells. Tigecycline induced deficiency of respiratory chain by disturbing mitochondrial translation process and showed therapeutic potential in liver cancer. For liver cancer cells extremely insensitive to tigecycline, a compounds screen was applied to identify MEK inhibitors as synergistic drugs to tigecycline-insensitive liver cancer cells. Mechanistically, sustained activation of EGFR-ERK1/2-MYC cascade conferred the insensitivity to tigecycline, which was mediated by enhanced secretion of EREG and AREG. Moreover, glycolytic enzymes, such as HK2 and PKM2 were upregulated to stimulate glycolysisin a MYC-dependent manner. Tigecycline induced respiratory chain deficiency in combination with cutting off EGFR-ERK1/2-MYC cascade by MEK inhibitors or EGFR inhibitors, resulting in decrease of both oxidative phosphorylation and glycolysis in liver cancer cells. INTERPRETATION: Our study proved that blocking EGFR-ERK1/2-MYC cascade combined with tigecycline could be a potential therapeutic strategy for liver cancer. FUNDING: This work was funded by grants from the National Natural Science Foundation of China (82073039,82222047, 81920108025), Program of Shanghai Academic/Technology Research Leader (22XD1423100), Shanghai Municipal Science and Technology Project (20JC1411100), 111 Project (B21024), Innovative Research Team of High-level Local Universities in Shanghai (SHSMU-ZDCX20212700, SHSMU-ZDCX20210802) and Shanghai Jiao Tong University School of Medicine (YG2019GD01).

Analysis of the clinical characteristics of tigecycline-induced hypofibrinogenemia.

Knowledge regarding the association between hypofibrinogenemia and tigecycline is based mainly on case reports. However, the clinical features of tigecycline-induced hypofibrinogenemia are unclear. We collected 20 patients (16 males and 4 females) with tigecycline-induced hypofibrinogenemia by searching the Chinese and English databases from June 2005 to May 2021, with a median age of 63.5 years (range 39∼90 years). Hypofibrinogenemia developed at a median of 9 days (range 2∼35 days). Most patients had no typical clinical manifestations, and only a few patients had bleeding and ecchymosis. Fibrinogen levels gradually decreased from 3.98 ± 2.05 g/L to 0.87 ± 0.45 g/L (P = 0.000), and the activated partial thromboplastin time (APTT) increased from 38.26 ± 8.80 s to 83.43 ± 47.23 s (P = 0.002). Fibrinogen levels in all patients recovered to the normal range within a median of 4 days (range 1∼12 days) after tigecycline cessation. Our results suggest that fibrinogen levels should be closely monitored in patients treated with tigecycline, specifically patients who may have renal insufficiency or patients with long-term use.

Serum concentration as a predictor of tigecycline-induced hypofibrinogenemia in critically ill patients: A retrospective cohort study.

OBJECTIVES: This study aimed to determine the thresholds of serum concentration as a predictor of tigecycline (TGC)-induced hypofibrinogenemia (HF) in critically ill patients. METHODS: A retrospective cohort study was conducted in intensive care unit patients treated with TGC. The clinical data and serum concentration were extracted from the patients' electronic medical records. Patients were divided into an HF group and a normal group according to fibrinogen value. The receiver operating characteristic curves and logistic regression were used to derive serum concentration thresholds and quantify the association between exposure thresholds and HF while adjusting for confounders. RESULTS: In total, 100 patients were included. The receiver operating characteristic curves analysis showed that TGC concentration parameters were strongly predictive of HF. Adjusting for duration of TGC, serum concentration at the 6 hours after the dosing (C1/2) ≥ 0.645 mg/l, area under the concentration-time curve over a 24-hour period (AUC 0-24) ≥ 20.76 mg·h/l, and serum concentration of 30 minutes before next dose (Cmin) ≥ 0.455 mg/l were associated with a three- to five-fold increased risk of TGC-induced HF in logistic regression. CONCLUSION: The findings from this study provide evidence that TGC exposure is highly predictive of HF, with an approximately three- to five-fold increased risk. Serum concentration at the 6 hours after the dosing (C1/2) ≥ 0.645 mg/l with best area under the receiver operating characteristic curve and negative predictive value appears to be the most appropriate toxicity threshold.

Tigecycline-Associated Coagulopathy: A Single-Center Retrospective Analysis.

INTRODUCTION: The purpose of this study was to assess clinical characteristics and risk factors for tigecycline-associated prothrombin time (PT) and activated partial thromboplastin time (aPTT) prolongation. METHODS: We performed a retrospective analysis on coagulation parameters before and during tigecycline treatment in 55 patients in our hospital with severe infections, mainly pneumonia caused by Acinetobacter baumannii. Patients were divided into different groups according to prolongation of PT and aPTT, and clinical features involved were explored. Univariate and multivariable binary logistic regression analyses were used to identify risk factors for tigecycline-associated PT and aPTT increase. RESULTS: We found that PT values increased from 12.73 ± 1.87 to 13.86 ± 2.06 during the treatment compared with premedication (p < 0.001), and the aPTT level prolonged significantly from 33.63 ± 11.24 to 38.15 ± 11.81 (p < 0.001). The multivariate analyses identified 2 variables that were associated with tigecycline-induced PT prolongation: albumin level (p = 0.018) and weight-adjusted tigecycline dosage (p = 0.005). In addition, treatment duration was the only risk factor for tigecycline-induced aPTT prolongation (p = 0.043). CONCLUSION: Albumin level, weight-adjusted tigecycline dosage, treatment duration may serve as risk indicators for tigecycline-associated coagulation dysfunction. Physicians should be careful with coagulation disorder when prescribing tigecycline in clinical practice, especially in patients with risk factors.

Risk Factors for Tigecycline-Associated Hepatotoxicity in Patients in the Intensive Care Units of 2 Tertiary Hospitals: A Retrospective Study.

Tigecycline is a broad-spectrum antibacterial agent. As the incidence of multidrug-resistant bacterial infections has increased in intensive care units (ICUs) over the past decades, tigecycline is often used in ICUs. Information about tigecycline-associated hepatotoxicity in ICU patients is limited. To investigate the potential risk factors for tigecycline-associated hepatotoxicity in ICU patients, 148 patients from 2 centers who had received tigecycline for at least 4 days were retrospectively analyzed. Hepatotoxicity was classified according to the National Cancer Institute Common Terminology Criteria for Adverse Events (5.0) grading system. As a result, 33.8% of patients experienced hepatotoxicity events in the ICU. The multivariate analysis showed that an albumin concentration <25 g/L at baseline (odds ratio, 3.714; 95%CI, 1.082-12.744; P = .037) and treatment duration (odds ratio, 1.094; 95%CI, 1.032-1.160; P = .003) were significantly correlated with tigecycline-associated hepatotoxicity. The median time to onset of hepatotoxicity was 8.0 days. The median duration ICU stay and the in-hospital mortality rate were not different between the hepatotoxicity group and the nonhepatotoxicity group (33.5 days (interquartile range, 21.0-72.0) vs 31.0 days (interquartile range, 21-62.5), P = .850; 38.0% vs 43.8%; P = .504). Therefore, close monitoring of liver function is recommended for patients with baseline albumin concentrations <25 g/L or for patients who receive tigecycline therapy for >8 days.

Drug use investigation on the safety and efficacy of tigecycline in Japan (all-case post-marketing surveillance).

INTRODUCTION: We conducted a drug use investigation to investigate the safety and efficacy of tigecycline, which has been approved for clinical use for the treatment of multidrug-resistant gram-negative infections in Japan. METHODS: This was an open-label, observational, multicenter cohort study that included all patients who received tigecycline. RESULTS: A total of 116 patients were registered between December 2012 and April 2016 and all of them were evaluated for safety and efficacy. Among them, 64 patients aged ≥65 years (55.2%) and five children aged <15 years (4.3%) were included. Of these patients, 47 (40.5%) met the approved indications of tigecycline. Adverse drug reactions (ADRs) were observed in 41 patients (35.3%) with a total of 74 events. Serious ADRs were observed in 15 patients (12.93%) with a total of 33 events. There were 42 deaths, and 6 of these were considered to be caused by ADRs. Among the 116 patients, 65 achieved clinical response at the end of the observation period, and the efficacy rate was 73.9%. Furthermore, 46 patients were assessed as "cure" at the test of cure visit, and the cure rate was 59.0%. The eradication rate was 47.5% at the end of the observation period. Classified by pathogenic bacteria, the eradication rate of patients infected with the approved pathogens was 54.5%. CONCLUSIONS: Tigecycline was well-tolerated, and no additional safety concerns were noted. It was effective considering that most patients had poor physical conditions. The overall benefit-risk balance of tigecycline was favorable.

Prevalence and risk factors of tigecycline-induced liver injury: A multicenter retrospective study.

OBJECTIVE: We conducted this multicenter retrospective study to evaluate the prevalence, clinical patterns, and risk factors for tigecycline-induced liver injury, which is a type of drug-induced liver injury (DILI). METHODS: Inpatients receiving intravenous tigecycline for ≥7 days were included. Patient information was collected to assess possible DILIs. The pattern and severity of tigecycline DILI were evaluated. A multivariable logistic regression model was used to identify the independent risk factors associated with tigecycline DILI. RESULTS: A total of 986 patients were identified and 397 patients were included in this study. The prevalence of tigecycline DILI was 10.3% (95% confidence interval [CI] = 7.51-13.7%). The most common type of tigecycline DILI was cholestatic, with mild severity observed in most cases. Abnormal baseline alanine aminotransferase levels (odds ratio [OR] = 3.11, 95% CI = 1.55-6.24, P = 0.001), intensive care unit admission (OR = 2.63, 95% CI = 1.32-5.36, P = 0.006), and treatment length (in weeks) (OR = 1.25, 95% CI = 1.05-1.49, P = 0.011) were independent risk factors for tigecycline DILI. CONCLUSION: Our results indicate that the prevalence of tigecycline DILI is high, and that the patients at risk should receive special attention.

A case report of drug-induced liver injury after tigecycline administration: histopathological evidence and a probable causality grading as assessed by the updated RUCAM diagnostic scale.

BACKGROUND: There have been no reports of tigecycline-associated drug-related liver injury (DILI) identified by histopathological assistance and causal assessment method. We reported the histopathological manifestations for the first time and described tigecycline-associated liver injury's pattern, severity, duration, and outcome. CASE PRESENTATION: A 68-year-old male with post-liver transplantation was given high-dose tigecycline intravenously (loading dose 200 mg, followed by 100 mg every 12 h) combined with polymyxin B (50,000 units by aerosol inhalation every 12 h) for hospital-acquired pneumonia caused by carbapenem-resistant Klebsiella pneumoniae. At the same time, tacrolimus was discontinued. Liver function was initially normal but started to decline on day 4 of tigecycline. Reducing the dose of tigecycline and resuming tacrolimus could not reverse the deterioration. Therefore, a liver puncture biopsy was performed for further diagnosis, with histopathological findings being cytotoxic injury. The updated RUCAM scale was used to evaluate the causal relationship between tigecycline and liver injury, with the result of 7 points indicating a "probable" causality grading. Methylprednisolone was initiated to treat DILI that was determined to be Grade 1 cholestatic injury. Total bilirubin and transaminase levels returned to normal on day 4 and 11 after tigecycline withdrawal, respectively. Monthly outpatient follow-up showed that the patient's liver function stayed normal. CONCLUSIONS: This case possessed a significant reference value for differential diagnosis and treatment prognosis of tigecycline-associated DILI. With early diagnosis and timely management, the tigecycline-associated DILI of this patient was successfully reversed.

Impact of drug safety warnings and antimicrobial stewardship programme implementation on tigecycline prescribing: a prospective quasi-experimental interrupted time series analysis.

BACKGROUND: Tigecycline is the first member of the glycylcyclines. Both the FDA (2010 and 2013) and the EMA (2011) issued safety warnings describing an increased mortality risk associated with tigecycline compared with other antibiotics treating severe infections. One of the best strategies to optimize antimicrobial therapies is through the establishment of antimicrobial stewardship programmes (ASPs) in hospitals. In June 2011, our ASP was implemented. OBJECTIVES: To analyse trends in tigecycline prescription, after drug safety warning announcements by regulatory agencies and after an ASP implementation. METHODS: A 6 year prospective observational study of tigecycline use was performed, including all consecutive adult patients treated with at least one dose during the 6 years after approval of the drug for its use in the hospital. The primary outcome was tigecycline consumption assessed by DDD/100 bed-days. A segmented linear regression model for interrupted time series (ITS) was designed to detect any significant trend changes. RESULTS: A total of 524 patients were included. After the FDA warning alert, tigecycline consumption decreased by 35.9%. Moreover, following the ASP implementation, a dramatic reduction in tigecycline prescription by 67.3% was observed. CONCLUSIONS: The role of the ASP was essential to establish adequate control of prescriptions, collaborating with the clinicians in a better adaptation of the tigecycline indication.

Acute pancreatitis caused by tigecycline: A case report and literature review.

RATIONALE: There is evidence that tigecycline has broad-spectrum antibiotic activity against a variety of complicated infections. However, adverse effects are inevitable, including gastrointestinal side effects such as nausea, vomiting, and diarrhea; in 2006, acute pancreatitis was also brought into the side-effect list after postmarketing surveillance. Here, we present a case of tigecycline-induced acute pancreatitis. PATIENT CONCERNS: An 87-year-old female patient with urinary tract infection received an intravenous drip of tigecycline for 6 days, after which she developed abdominal distension, vomiting, abdominal pain, and abdominal rigidity. DIAGNOSIS: The patient was suspected to have tigecycline-induced acute pancreatitis. INTERVENTIONS: Tigecycline was discontinued immediately, and the patient received a series of immediate treatments including an indwelling gastric tube for continuous gastrointestinal decompression and inhibition of gastric acid and pancreatic enzyme secretion. OUTCOMES: Following initial interventions, we observed that the patient's symptoms improved significantly, and abdominal distension, vomiting, abdominal pain, and abdominal rigidity were slightly relieved. After 5 days of follow-up, blood lipase and amylase levels decreased to normal levels. Unfortunately, the patient developed convulsions during the use of multiple antibiotics after 1 week and then died of septic shock and acute liver failure. LESSONS: Acute pancreatitis caused by tigecycline is rare. However, in the application of antibiotics, the possibility of adverse effects must be considered, and antibiotics should be used reasonably. If the patient has relevant symptoms, it is necessary to stop using tigecycline immediately, carry out symptomatic treatment, and change to other types of antibiotics for antibacterial treatment.

Tigecycline-Induced Tooth Discoloration in Children Younger than Eight Years.

Tetracycline may cause tooth discoloration when used in young children during tooth development. Whether tigecycline, a tetracycline derivative, has either a similar adverse event or not remains unclear. We assessed the discoloration of the permanent teeth of patients <8 years old after tigecycline exposure. These patients were identified through a retrospective chart review in a Chinese children's hospital. Those who had at least one erupted permanent tooth after tigecycline exposure were interviewed, examined, and photographed by an experienced pediatric dentist and independently assessed by another senior dentist to detect tetracycline-like tooth discoloration. We identified 101 patients who were exposed to tigecycline, 12 of whom were included. The mean daily dose of tigecycline was 2.3 mg/kg of body weight (standard deviation, 0.6), and the median duration was 12.5 days (interquartile range [IQR], 8.0 to 19.3). The median age of exposure was 5.2 years (IQR, 4.5 to 7.4), and the median age of dental examination was 9.1 years (IQR, 9.0 to 10.3). Two patients (16.7%) developed yellow discoloration: a girl having yellow discoloration with white-to-yellow opacities in the upper lateral incisors and lower incisors and a boy with a suspicious buccal yellow discoloration and enamel dysplasia in the second molars. The incidence and extent of tigecycline-associated dental adverse events remain unclear due to the small sample size and inadequate follow-up period.

Tigecycline-induced life-threatening coagulopathy in a patient with a Mycobacterium abscess: a case report and step-by-step diagnostic approach.

Tigecycline is a broad-spectrum antibiotic that is indicated in the treatment of complicated intra-abdominal infections and complicated skin and skin and soft-tissue infections. We report the case of a 53-year old kidney transplant patient with a severe Mycobacterium abscess who developed life-threatening coagulopathy after initiation of tigecycline therapy. Further analysis revealed a severe hypofibrinogenemia. A few case reports previously described an association between tigecycline and prolongation of clotting time. Our case confirms an uncommon yet possibly life-threatening side-effect of tigecycline. Medical practitioners should be aware of this potential coagulopathy and we recommend routine monitoring of coagulation parameters in patients receiving tigecycline.

Hypofibrinogenemia induced by high-dose tigecycline-case report and review of literature.

RATIONALE: Extensive off-label use may affect the safety profile of tigecycline. Tigecycline-associated hypofibrinogenemia is potentially life threatening, although the frequency of life-threatening reactions is unknown and their incidence is easily overlooked. We report a case of 2 instances of treatment with high-dose tigecycline, each of which presented with hypofibrinogenemia. PATIENT CONCERNS: An 86-year-old male patient was treated twice with high-dose tigecycline and presented with hypofibrinogenemia both times. The decrease in fibrinogen occurred within 3 to 7 days of tigecycline treatment. Other coagulation parameters had slightly prolonged values. DIAGNOSES: Coagulopathy and hypofibrinogenemia. INTERVENTIONS: We discontinued the tigecycline. OUTCOMES: The fibrinogen level normalized within 5 days after the withdrawal of tigecycline. Following 80 days of hospitalization, the patient was transferred to the rehabilitation hospital for further treatment. LESSONS: We suggest routine strict monitoring of coagulation parameters, particularly fibrinogen. Attention should be paid to below-normal fibrinogen levels due to increased bleeding risk and severity of reaction at fibrinogen levels below 1 g/L.