A critically ill patient after a colchicine overdose below the lethal dose: a case report

Effect of increasing doses of colchicine on the treatment of 333 COVID-19 inpatients

BACKGROUND

Previous research done in Bulgaria demonstrated a fivefold reduction in mortality from COVID-19 with increased doses of colchicine from two hospitals in the country. We report here a further 333 cases of COVID-19 inpatients, treated with different doses of colchicine and its effect on mortality.

MATERIALS AND METHODS

A case-control comparison from two additional hospitals was conducted between increased doses of colchicine and added bromhexine to standard of care (SOC) versus current SOC. Risk and odds ratio, as well as subgroup analysis, was conducted with newly reported data, alongside aggregate data from all hospital centers to determine the extent of mortality reduction in COVID-19 inpatients.

RESULTS

There was a clear reduction in the mortality of inpatients with increasing doses of colchicine-between twofold and sevenfold. Colchicine loading doses of 4 mg are more effective than those with 2 mg. Despite these doses being higher than the so-called "standard doses," colchicine inpatients experienced lower mortality than SOC patients (5.7% vs. 19.53%). This mortality benefit was evident in different age subgroups, with a 4-mg loading dose of colchicine proving slightly superior to a 2-mg loading dose. Colchicine led to an overall relative risk reduction of 70.7%, with SOC patients having 3.91 higher odds of death. The safety of the doses was not different than the reported in the summary of product characteristics.

CONCLUSION

Inpatients in Bulgaria with added colchicine and bromhexine to SOC achieved better clinical and mortality outcomes than those on SOC alone. These results question the World Health Organization-recommended strategy to inhibit viral replication. We posit that our treatment strategy to inhibit the Severe acute respiratory syndrome coronavirus 2 entry into the cell with inhaled bromhexine and the hyperactivated NLRP3 inflammasome with higher doses of colchicine, prevents the development of cytokine storm. The timing of the initiation of treatment seems critical.

Colchicine: the good, the bad, the ugly and how to minimize the risks

Colchicine has an important role in managing various conditions, including gout, familial Mediterranean fever, amyloidosis, Behçet's syndrome, recurrent pericarditis and calcium pyrophosphate deposition disease. The adverse effect profile of colchicine is well understood. However, due to its narrow therapeutic index, colchicine has been associated with overdose and fatalities. When ingested in toxic amounts, the mainstay of management is supportive care. Strategies to minimize the risk of colchicine poisoning can focus on three broad causes: unauthorized access, intentional overdose and inappropriate dosing. Culturally safe and appropriate education about storage and appropriate use of colchicine is essential to minimize the risk of overdose.

Photolysis and cytotoxicity of the potentially toxic composition of daylily flower: colchicine

The photolysis of colchicine under ultraviolet and visible light irradiation was studied by ultraviolet (UV) scanning and HPLC-MS. The photoproduct was proposed and the cytotoxicity change before and after irradiation was investigated. Results showed that both ultraviolet and visible light irradiation could effectively degrade colchicine into deacetamido-lumicolchicine. The process conformed to first-order kinetics, in which a high degradation rate (K = 0.5862 h^− 1) was observed when colchicine was dissolved in ethanol and irradiated by UV light. Cell viability and cell cycle studies proved that a photolysis treatment of colchicine could weaken the cytotoxicity effectively. Colchicine inhibited the division of BRL 3 A cells in G2/M phase with an IC₅₀ value of 0.48 µg/mL, while the toxic effect could be reduced significantly with IC₅₀ 2.1 µg/mL when colchicine was exposed to UV irradiation. Results are beneficial to the toxicity elimination of colchicine in the processing of daylily flower in food industry, and can also provide photochemistry reference for colchicine-related studies.

A Review of the Rational and Current Evidence on Colchicine for COVID-19

The current coronavirus disease (COVID-19) pandemic has affected millions of individuals worldwide. Despite extensive research efforts, few therapeutic options currently offer direct clinical benefits for COVID-19 patients. Despite the advances in our understanding of COVID-19, the mortality rates remain significantly high owing to the high viral transmission rates in several countries and the rise of various mutations in the SARS-CoV-2. One currently available and widely used drug that combines both anti-inflammatory and immunomodulatory actions is colchicine, which has been proposed as a possible treatment option for COVID-19. Colchicine still did not get much attention from the medical and scientific communities despite its antiinflammatory and immunomodulatory mechanisms of action and positive preliminary data from early trials. This literature review article provides the scientific rationale for repurposing colchicine as a potential therapy for COVID-19. Further, we summarize colchicine's mechanisms of action and possible roles in COVID-19 patients. Finally, we supplement this review with a summary of the doses, side effects, and early efficacy data from clinical trials to date. Despite the promising early findings from multiple observational and clinical trials about the potential of colchicine in COVID-19, the data from the RECOVERY trial, the largest COVID-19 randomized controlled trial (RCT) in the world, showed no evidence of clinical benefits in mortality, hospital stays, or disease progression (n = 11340 patients). However, multiple other smaller clinical trials showed significant clinical benefits. We conclude that while current evidence does not support the use of colchicine for treating COVID-19, the present body of evidence is heterogeneous and inconclusive. The drug cannot be used in clinical practice or abandoned from clinical research without additional large RCTs providing more robust evidence. At present, the drug should not be used except for investigational purposes.

Progress in the management of acute colchicine poisoning in adults

Colchicine is a tricyclic, lipid-soluble alkaloid which has long been used to treat gout and many immunological diseases. Due to its narrow therapeutic window and long half-life of elimination, colchicine overdose occurs occasionally. Unfortunately, some patients lost their lives because of colchicine overdose or suicide. Acute colchicine poisoning can lead to original gastrointestinal disorders, shock, progressive multiple organ failure, and myelosuppression. Although many researchers in the world performed lots of research, there are currently no specific antidotes for colchicine poisoning. Meanwhile, there are no management guidelines to treat patients with acute colchicine poisoning until now. Herein, we systematically elaborate on the clinical features and progress in the management of acute colchicine poisoning in adults according to the previous literature. This paper will provide some valuable and available information for clinicians.

Relationship between toxicity and oxidative stress of the nanoencapsulated colchicine in a model of Drosophila melanogaster

Drug repurposing allows searching for new biological targets, especially against emerging diseases such as Covid-19. Drug colchicine (COL) presents recognized anti-inflammatory action, while the nanotechnology purpose therapies with low doses, efficacy, and decrease the drug's side-effects. This study aims to evaluate the effects of COL and colchicine nanocapsules (NCCOL) on survival, LC50, activity locomotor, and oxidative stress parameters, elucidating the toxicity profile in acute and chronic exposure in Drosophila melanogaster. Three-day-old flies were investigated into groups: Control, 0.001, 0.0025, 0.005, and 0.010 mg/mL of COL or NCCOL. The survival rate, open field test, LC50, oxidative stress markers (reactive species (RS) production, thiobarbituric acid reactive substances), antioxidant enzyme activity (catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase), protein thiols, nonprotein thiols, acetylcholinesterase activity, and cell viability were measured. As a result, acute exposure to the COL decreases the number of crosses in the open field and increases CAT activity. NCCOL reduced RS levels, increased lipoperoxidation and SOD activity. Chronic exposure to the COL and NCCOL in high concentrations implied high mortality and enzymatic inhibition of the CAT and AChE, and only the COL caused locomotor damage in the open field test. Thus, NCCOL again reduced the formation of RS while COL increased. In this comparative study, NCCOL was less toxic to the antioxidant system than COL and showed notable involvement of oxidative stress as one of their toxicity mechanisms. Future studies are needed to elucidate all aspects of nanosafety related to the NCCOL.

Nanoscale characterization of drug-induced microtubule filament dysfunction using super-resolution microscopy

BACKGROUND

The integrity of microtubule filament networks is essential for the roles in diverse cellular functions, and disruption of its structure or dynamics has been explored as a therapeutic approach to tackle diseases such as cancer. Microtubule-interacting drugs, sometimes referred to as antimitotics, are used in cancer therapy to target and disrupt microtubules. However, due to associated side effects on healthy cells, there is a need to develop safer drug regimens that still retain clinical efficacy. Currently, many questions remain open regarding the extent of effects on cellular physiology of microtubule-interacting drugs at clinically relevant and low doses. Here, we use super-resolution microscopies (single-molecule localization and optical fluctuation based) to reveal the initial microtubule dysfunctions caused by nanomolar concentrations of colcemid.

RESULTS

We identify previously undetected microtubule (MT) damage caused by clinically relevant doses of colcemid. Short exposure to 30-80 nM colcemid results in aberrant microtubule curvature, with a trend of increased curvature associated to increased doses, and curvatures greater than 2 rad/μm, a value associated with MT breakage. Microtubule fragmentation was detected upon treatment with ≥ 100 nM colcemid. Remarkably, lower doses (< 20 nM after 5 h) led to subtle but significant microtubule architecture remodelling characterized by increased curvature and suppression of microtubule dynamics.

CONCLUSIONS

Our results support the emerging hypothesis that microtubule-interacting drugs induce non-mitotic effects in cells, and establish a multi-modal imaging assay for detecting and measuring nanoscale microtubule dysfunction. The sub-diffraction visualization of these less severe precursor perturbations compared to the established antimitotic effects of microtubule-interacting drugs offers potential for improved understanding and design of anticancer agents.

Severe Colchicine Intoxication: A Case Report and Review of Literature in Adults

Colchicine is used in the treatment of multiple diseases such as gout and auto-immune diseases. Although cases of multiorgan failure have been described in adults with doses usually higher than 0.8 mg/kg, the epidemiology data are scarce and the intoxication mechanisms are not well-known. The authors present the case of a 66-year-old male patient, with a medical history of depression, admitted to the emergency room (ER) due to intentional colchicine ingestion after taking 90 mg (approximately 1.125 mg/kg) 12 hours prior to medical evaluation. Besides some dizziness and sleepiness, he showed no other alteration in the physical examination. After the administration of activated charcoal, he was transferred to the intensive care unit (ICU). The laboratory findings showed mild hepatic dysfunction, acute kidney injury, and metabolic lactic acidosis. Despite treatment, severe clinical worsening with multiorgan failure, including respiratory failure complicated with multiple episodes of cardiac dysrhythmias and finally with persistent cardiac arrest, lead to the patient’s death after 13 hours of admission in the ER. Among drug intoxications, high doses of colchicine ingestion can lead to rapid multiorgan dysfunction, and patients with a severe overdose can experience irreversible multiorgan failure without presenting the typical initial gastrointestinal symptoms. Thus, it is necessary for the physicians to be alert to these situations and to be aware of the epidemiological data and clinical profile of this specific poisoning that should be managed in ICU. The authors perform a review of the cases of colchicine poisoning reported in adults between 2017 and 2019 and the differences in clinical management and outcomes.

The Ugly Side of Colchicine

We report a rare case of a 32-year-old male who ingested 32.4 to 54 mg of colchicine and presented after 44 hours. He developed progressive multiple organ failure with shock, acute kidney failure, troponemia, pancytopenia, absolute neutropenia, disseminated intravascular coagulation, acute liver failure, rhabdomyolysis, and lactic acidosis. He also developed electrolyte abnormalities and refractory hypoglycemia. Initial treatment consisted of activated charcoal, fluids, and broad-spectrum antibiotics with supportive treatment of mechanical ventilation, hemodialysis, vasopressors, N-acetylcysteine, colony-stimulating factors, and blood products. Literature shows potential benefit of colchicine-specific Fab fragments for acute toxicity with limited studies and is not currently available in the United States. Further research for N-acetylcysteine protocol for acute liver failure in colchicine toxicity and potential use of colchicine-specific Fab fragments is needed. Our case demonstrates the importance of early use of activated charcoal for ingestion overdose with the incorporation of poison control into multidisciplinary team for coordinated patient care.

Sudden Death Following Suicide with Colchicine and Chloroquine

Poisoning with any of the colchicine or chloroquine drugs is rare. These drugs exert therapeutic and toxic effects on tissues by different mechanisms. Colchicine is used to treat a number of rheumatologic diseases and heart problems. In addition, chloroquine is used to treat malaria and some inflammatory diseases. There is a small gap between the therapeutic and toxic doses of these drugs. Gastrointestinal symptoms are the initial causes of poisoning with these drugs and then widespread organ failure in later stages can lead to sudden cardiac death. We introduce a case of concurrent poisoning with both drugs, in which the patient presented with a headache, nausea, and vomiting several hours after suicide. On the 1^st day, the patient's status was stable, but on the 2^nd day, the patient suddenly becomes ill and died even though the patient received supportive therapy. Concurrent poisoning with chloroquine and colchicine is extremely lethal, and early aggressive management is recommended even in an apparently stable patient.

Acute Colchicine Poisoning Causes Endotoxemia via the Destruction of Intestinal Barrier Function: The Curative Effect of Endotoxin Prevention in a Murine Model

BACKGROUND

Colchicine binds to intracellular tubulin and prevents mitosis. Colchicine is also used as an anti-inflammatory drug. Meanwhile, excess administration of medication or accidental ingestion of colchicine-containing plants can cause acute colchicine poisoning, which initially results in gastrointestinal effects that may be followed by multiorgan dysfunction. However, the mechanism of colchicine poisoning remains unclear, and there are no standard therapeutic strategies.

AIMS

We focused on intestinal barrier function and attempted to reveal the underlying mechanism of colchicine poisoning using an animal model.

METHODS

Colchicine was orally administered to C57Bl/6 mice. Then, we performed histopathological analysis, serum endotoxin assays, and intestinal permeability testing. Additionally, the LPS-TLR4 signaling inhibitor TAK-242 was intraperitoneally injected after colchicine administration to analyze the therapeutic effect.

RESULTS

We observed villus height reduction and increased numbers of apoptotic cells in the gastrointestinal epithelium of colchicine-treated mice. Both intestinal permeability and serum endotoxin levels were higher in colchicine-treated mice than in control mice. Although colchicine-poisoned mice died within 25 h, those that also received TAK-242 treatment survived for more than 48 h.

CONCLUSION

Colchicine disrupted intestinal barrier function and caused endotoxin shock. Therapeutic inhibition of LPS-TLR4 signaling might be beneficial for treating acute colchicine poisoning.

Efficacy and safety of colchicine in inflammatory skin diseases: a retrospective, monocentric study in a large tertiary center

Introduction: Colchicine is an ancient, but rarely used drug. Little data exist on its efficacy and safety in patients suffering from skin diseases. The objective of our study was to determine whether colchicine showed favorable efficacy and safety in our patients during the last 20 years.Methods: The hospital database was searched for patients treated with colchicine in the last 20 years (January 1, 1998 to December 31, 2017). Overall, total of 41 patients were included in our study.Results: In 63.4% of all patients, either a complete response or an improvement of disease was observed. Adverse events occurred rarely.Discussion: Colchicine is an effective and safe treatment.

Clinical outcomes after colchicine overdose: A case report

RATIONALE

Colchicine can inhibit cell division and intracellular transport in affected organs by fixing intracellular tubulin and preventing its polymerization into microtubules. A lethal dose of colchicine is considered to be 0.8 mg/kg. The wide distribution of colchicine through 70% of the body following an overdose makes it difficult to eliminate.

PATIENT CONCERNS

A 56-year-old man with a clear history of colchicine overdose was admitted to our hospital nearly 40 hours after taking 12 mg (0.17 mg/kg) of colchicine. He had a history of gout and chronic kidney disease. As the disease progressed, he showed most of the clinical manifestations and pathological features of colchicine overdose.

DIAGNOSES AND INTERVENTIONS

Colchicine overdose was clear, with symptoms of multiple organ failure including primary gastrointestinal failure, bone marrow hematopoietic inhibition, rhabdomyolysis, cardiac damage, hepatocyte damage. The patient developed secondary septic shock, renal failure, circulatory failure, and respiratory failure. We performed continuous renal replacement therapy and gastric lavage, and administered norepinephrine, frozen plasma, proton-pump inhibitors, adenosylmethionine, antibiotics, granulocyte colony stimulating factor, and total parenteral nutrition.

OUTCOMES

The patient rapidly developed complete hematopoietic function inhibition, gastrointestinal failure, and cardiac damage 32 hours after admission. Sustained severe infection and circulatory instability caused a progressive deterioration of respiratory function. Tracheal intubation was performed but the patient continued to deteriorate, and death occurred approximately 132 hours after admission.

LESSONS

Excessive colchicine levels cause continuous organ damage due to extensive tissue distribution, eventually leading to multiple organ failure. Colchicine metabolism is delayed in patients with liver or kidney dysfunction, and even a low dose of colchicine may result in poisoning in these individuals. Early diagnosis and reduction of colchicine levels is critical to improve prognosis, and colchicine poisoning should be considered in patients with poor liver or kidney function even when the ingested dose is low.

Recent progress in nanomaterial-based assay for the detection of phytotoxins in foods

Phytotoxins refers to toxic chemicals derived from plants. They include both secondary metabolites that are dose-dependently toxic and allergens that can cause anaphylactic shock in sensitive individuals. Detecting phytotoxins in foods is increasingly important. Conventional methods for detecting phytotoxins lack sufficient sensitivity and operational convenience. Nanomaterial-based determination assays show great competence in fast and accurate sensing of trace substances. In the present review, representative phytotoxin categories of alkaloids, cyanides, and proteins are discussed. Application of notable nanomaterials, e.g. carbon nanotubes, graphene oxide, magnetic nanoparticles, metal-based nanotools, and quantum dots, in specific sensing strategies to fit the physiochemical properties of the target toxins are summarized. Nanomaterials mainly play four roles in phytotoxin detection: 1) analyte enricher; 2) sensor structure mediator; 3) target recognizer or reactant; 4) signaling agent. Great achievements have been made in the detection of trace plant-derived toxins in food matrices, yet there are still challenges awaiting further investigation.