Tachon Syndrome: Rare Side Effect of Articular Injections of Corticosteroids. A Report of Two Cases

Thermal imaging of local skin temperature as part of quality and safety assessment of injectable drugs

Injection of high-quality drugs can occasionally cause unexpected and unexplained local complications. As the current standard for drug quality control does not include an assessment of the local irritation effects of drugs, this effect may cause postinjection complications. Simultaneously, local irritation effects of the drugs can be assessed based on local tissue inflammation. The dynamics of local temperature can assess inflammation. Infrared monitoring of local skin temperature dynamics at subcutaneous, intramuscular, and intravenous injection sites of drugs under experimental and clinical conditions can improve their quality and safety. Therefore, there is a need to include dynamic thermography in the standard of biological evaluation of the quality and safety of drugs in the dosage form "solution for injections." This eliminates the local irritation and necrotizing activity of drugs and minimizes the development of local pain syndrome, aseptic inflammation, necrosis, and abscess.

Hypertonic Activity of Injection Solutions Can Cause Post-injection Complications (Review)

Introduction. A review of the scientific literature showed that the current standards for assessing the quality of drugs does not include an assessment of the osmotic activity of drug solutions and their local irritant effect on tissues at the sites of subcutaneous, intramuscular and intravenous injections. Therefore, currently injectable solutions considered to be of high quality may not have isotonic activity and high postinjection safety.

Text. A study of the concentration range of quality drug solutions ready for injection showed that the acceptable concentration value of the main ingredients is in the range of 0.01 to 76 %. Direct measurement with an osmometer of the osmotic activity of injection solutions, considered qualitative today, has shown that injection solutions can have hypotonic, isotonic and hypertonic activity and their osmotic activity can be in the range of 0 – 3900 mosmol/l water. Study of acidic activity of drug solutions showed that in accordance with pharmacopoeial requirements of drug quality modern quality drug solutions ready for injection can have acidic, neutral or alkaline activity. Solutions with hypertonic activity have been found to have a local irritant effect. Moreover, an increase in hypertonic activity of drug solutions increases their local irritant effect. It has been found that excessively high hypertonic activity of drug solutions may be the cause of the development of a local postinjection complication known as "Nicolaou syndrome", the cause of which has remained unknown for a long time. Nicolaou syndrome includes local pain syndrome, aseptic inflammation, necrosis, and abscess.

Conclusion. The authors conducted a literature review, the results of which led to conclusions and assumptions. Solutions containing drugs in concentrations greater than 10 % may have the highest hypertonic activity, which can cause excessive dehydrating, local irritating and cauterizing effects. Therefore, injections of such drugs are most dangerous with the development of post-injection necroses and abscesses. That is why timely dilution of concentrated drug solutions with water by 2–10 times increases injection safety. It is proposed to include the assessment of osmotic activity and local irritant effect of drug solutions in the standard of drug quality control.

Immediate hypersensitivity reactions to steroids and steroid containing medications

PURPOSE OF REVIEW

Although rare and counterintuitive, hypersensitivity reactions to corticosteroids have been reported since the 1950s. Delayed hypersensitivity reactions following cutaneous exposure (contact allergy) are well understood and principles of testing, as well as cross-reactivity patterns, have been established. In contrast, understanding of immediate hypersensitivity reactions and delayed hypersensitivity reactions after systemic exposure is evolving more slowly. However, progress has been made in the delineating of underlying pathogenic mechanisms and in the development of testing.

RECENT FINDINGS

IgE-mediated hypersensitivity reactions to corticosteroids have been described. It has been recognized that some, if not all of them, may be due to excipients in steroid formulations. Two excipients, polyethylene glycol and carboxymethylcellulose, seem of particular importance, but cases of reactions to polysorbate 80 and lactose have also been reported. The use of skin testing but also, increasingly, in-vitro methods such as basophil activation test is improving diagnostic accuracy.

SUMMARY

The recognition of the role of excipients is leading to a paradigm shift in our approach to immediate hypersensitivity to corticosteroids. Improved access to in-vivo and in-vitro testing will enhance our understanding of true corticosteroid immediate allergy.

Emerging Trend in the Pharmacotherapy of Osteoarthritis

Osteoarthritis (OA) is a degenerative joint disorder and one of the most prevalent diseases among the elderly population. Due to the limited spontaneous healing capacity of articular cartilage, it still remains challenging to find satisfactory treatment for OA. This review covers the emerging trends of pharmacologic therapies for OA such as traditional OA drugs (acetaminophen, non-steroidal anti-inflammatory drugs (NSAIDs), opioids, serotonin-norepinephrine reuptake inhibitors (SNRIs), intra-articular injections of corticosteroids, and dietary supplements), which are effective in pain relief but not in reversing damage, and are frequently associated with adverse events. Alternatively, disease-modifying drugs provide promising alternatives for the management of OA. The development of these emerging OA therapeutic agents requires a comprehensive understanding of the pathophysiology of OA progression. The process of cartilage anabolism/catabolism, subchondral bone remodeling and synovial inflammation are identified as potential targets. These emerging OA drugs such as bone morphogenetic protein-7 (BMP-7), fibroblast growth factor-18 (FGF-18), human serum albumin (HSA), interleukin-1 (IL-1) inhibitor, β-Nerve growth factor (β-NGF) antibody, matrix extracellular phosphoglycoprotein (MEPE) and inverse agonist of retinoic acid-related orphan receptor alpha (RORα) etc. have shown potential to modify progression of OA with minimal adverse effects. However, large-scale randomized controlled trials (RCTs) are needed to investigate the safety and efficacy before translation from bench to bedside.