Viral Infections and Cutaneous Drug-Related Eruptions

Infectious mononucleosis: new concepts in clinical presentation, epidemiology, and host response

PURPOSE OF REVIEW

Infectious mononucleosis (IM) is an infectious disease that presents clinically in only a small percentage of individuals despite almost universal infection with the causative agent. Here, we review the latest concepts in the clinical presentation, epidemiology, and host response of this disease.

RECENT FINDINGS

Several recently published papers/reviews describe IM as a condition caused by one of several etiologic agents including, cytomegalovirus (HHV-5), Roseola virus (HHV-6) and Toxoplasmosis amongst others; this review focuses on IM as solely caused by the human herpes virus 4 (HHV-4). Since the initial discovery of the virus in the 1960s and its subsequent discovery as the primary etiologic agent for IM it has been associated with several human cancers and autoimmune disorders. Recent published findings show a correlation between HHV-4 and the autoimmune disorder, multiple sclerosis (MS), suggesting earlier IM could possibly act as a causative factor. Considering the important links being made with IM to so many cancers and autoimmune disorders it is surprising that a standard investigative procedure has yet to be determined for this disease. A standard approach to the investigation of IM would ensure more cases are diagnosed, particularly atypical cases, this would benefit epidemiological studies, and more immediately help practitioners distinguish viral from bacterial throat infections, enabling them to treat accordingly.

SUMMARY

The understanding of the latest concepts in clinical presentation, epidemiology and host response to IM would benefit greatly from the introduction of a standard procedure for its investigation and diagnosis.

Vascular cutaneous manifestations of COVID-19 and RNA viral pathogens: a systematic review

BACKGROUND

COVID-19, the widely recognized and highly contagious respiratory tract infection, has had a substantial impact on the field of dermatology since its emergence in 2019. SARS-CoV-2, the causative virus of COVID-19, is classified as an RNA virus. Various skin-related symptoms have been reported in patients with COVID-19, most notably the distinctive purple-red acral rash resembling chilblain lesions, commonly referred to as 'COVID toe'; similarly, skin-related symptoms have been observed in connection with other RNA viruses.

OBJECTIVES

To explore the relationship between RNA viruses and their associated vascular cutaneous manifestations vs. those observed in patients infected with SARS-CoV-2.

METHODS

A systematic literature review was conducted using PubMed and medical subject heading terms related to RNA viruses and related skin manifestations.

RESULTS

In total, 3994 patients diagnosed with COVID-19 presenting with skin rashes were included. Chilblain-like lesions were most frequently observed (30.2%), followed by erythematous maculopapular/morbilliform rashes (9.1%) and urticarial rashes (4.7%). Of 8362 patients diagnosed with RNA viruses, more than half of the skin findings reported were erythematous/maculopapular/morbilliform rashes (52.3%), followed by unspecified (11.3%) and purpuric rashes (10.6%).

CONCLUSIONS

When comparing RNA viral infections with COVID-19 infection, we observed similarities in the reported skin manifestations and their presumed pathways, with many implicated in the proinflammatory response. Owing to the wide range of cutaneous symptoms associated with RNA viruses and our currently limited understanding of the underlying mechanisms, additional research is warranted to investigate the pathology behind viral-induced skin lesions.

Causes and Management of Cutaneous Adverse Drug Reactions: A Comprehensive Review

Cutaneous adverse drug reactions (CADRs) are one of the most broadly studied and rigorously researched conditions in recent dermatological advancements. Also termed as "toxidermia," they are heavily involved and are of utmost importance to be understood and studied in the modern healthcare industry. In simple terms, they are dermatological manifestations which result from systemic drug administration to patients. Since allopathy is influenced by the medicines and drugs provided to the patients, cutaneous skin eruptions are a common occurrence in recent times. It is a need of the hour to understand the causative factors for such skin eruptions and the correct management and handling of such disorders to provide better healthcare to patients. The withdrawal of the causative drug which induces the reaction plays a key role in treatment. The risk factors are to be thoroughly studied, and dosages must be in accordance with the patient's situation. They are some of the common public health problems. The age group which is affected is highly variable as people from all age groups can be affected. Those who are affected comprise approximately 10% of all hospitalized patients, and it is also observed in about 1-4% of people who are on multiple medications.

Immunological Mechanisms in Cutaneous Adverse Drug Reactions

Adverse drug reactions (ADRs) are an inherent aspect of drug use. While approximately 80% of ADRs are predictable, immune system-mediated ADRs, often unpredictable, are a noteworthy subset. Skin-related ADRs, in particular, are frequently unpredictable. However, the wide spectrum of skin manifestations poses a formidable diagnostic challenge. Comprehending the pathomechanisms underlying ADRs is essential for accurate diagnosis and effective management. The skin, being an active immune organ, plays a pivotal role in ADRs, although the precise cutaneous immunological mechanisms remain elusive. Fortunately, clinical manifestations of skin-related ADRs, irrespective of their severity, are frequently rooted in immunological processes. A comprehensive grasp of ADR morphology can aid in diagnosis. With the continuous development of new pharmaceuticals, it is noteworthy that certain drugs including immune checkpoint inhibitors have gained notoriety for their association with ADRs. This paper offers an overview of immunological mechanisms involved in cutaneous ADRs with a focus on clinical features and frequently implicated drugs.

No Additional Risk of Ampicillin Rash Among Pediatric Liver Transplant Recipients With Concurrent Epstein-Barr Virus Infection

BACKGROUND

Epstein-Barr virus (EBV) infection frequently develops in children undergoing liver transplantation (LT) because of mandated immunosuppressive therapy. There is a risk of ampicillin rash when penicillin derivatives are used in patients with EBV-associated infectious mononucleosis. Hence, the administration of penicillin derivatives may raise concerns about ampicillin rash in patients with high EBV loads. However, no studies confirmed the risk of administering penicillin derivatives to EBV-infected children after LT.

METHODS

This retrospective study was conducted at the largest pediatric transplantation center in Japan. We investigated all pediatric liver transplant recipients who received penicillin derivatives within 2 years of LT between 2014 and 2020. We separated the cohort into EBV-positive and EBV-negative groups to assess the frequency of ampicillin and antibiotic-associated rash.

RESULTS

Two hundred eighty-six liver transplant recipients were enrolled. There were 111 recipients in the EBV-positive group and 175 recipients in the EBV-negative group. In the EBV-positive group, 49 patients had high EBV DNA loads (≥1000 copies/µg DNA). None of the patients in either group developed ampicillin rash, and the frequency of antibiotic-associated rash did not differ [8/111 (7.2%) vs. 10/175 (5.7%), P = 0.797]. Additional subgroup analysis revealed no difference in the frequency of antibiotic-associated rashes regardless of the presence or absence of high EBV loads.

CONCLUSIONS

In this study, ampicillin rash was not observed, and antibiotic-associated rash was not associated with concurrent EBV infection. Penicillin derivatives can be used safely, even in liver transplant recipients with persistent asymptomatic EBV infection.

An observational study of severe cutaneous adverse reactions at a tertiary care teaching hospital

Background

The term severe cutaneous adverse reactions to drugs (SCAR) comprises of acute generalized exanthematous pustulosis (AGEP), drug reaction with eosinophilia and systemic symptoms complex (DRESS), Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS-TEN) and drug-induced erythroderma or exfoliative dermatitis (ED). The present study aims at describing the epidemiological and clinical profile, probable cause and the extent of morbidity and mortality in patients with severe cutaneous adverse drug reactions.

Methods

An observational study of all cases of SCAR presenting to our centre during the period from Jun 2018 to July 2019 was carried out.

Results

A total of 24 SCAR patients were studied. Most of the patients were in the age group of 11-20 years. The commonest reactions observed were SJS-TEN (54.2%) followed by DRESS (42%). Antibiotics are the most common cause of SJS-TEN, whereas almost all the drug groups were implicated equally in DRESS. No causative drug could be found in two of the SJS-TEN patients. These patients had raised atypical targetoid lesions as well as evidence of viral reactivation which could have been the probable trigger for the SCAR. A total of five patients (20.8%) died during treatment in hospital, and the percentage mortality was highest in SJS-TEN.

Conclusion

Nondrug aetiologies for SJS-TEN are on the rise, and this was observed in this study too. Viral reactivation may be the commonest aetiology in such cases, and the morphology of the rash can give a clue to such cases.

Practical Approach to Hypersensitivity to Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) in Children

BACKGROUND

We aimed to assess the real-life prevalence, patient profile, and clinical presentation of drug hypersensitivity to NSAIDs in children after an incidence of an adverse event during treatment, verified by a drug challenge test.

METHODS

We included 56 children, aged 4-18 years, referred to our allergy clinic due to the incidence of adverse reaction during treatment. Skin prick tests and a drug provocation test were performed in all patients. Diagnostics for persistent urticaria were performed.

RESULTS

In 56 patients suspected of drug allergy, we proved NSAID hypersensitivity in 17 patients (30.1%). In 84.9% (n = 47) of patients, the clinical manifestations of hypersensitivity revealed angioedema and urticaria. The most common culprit drug among NSAIDs in children was ibuprofen. Thirty-one (55.4%) reactions were immediate, and 25 (44.6%) were delayed or late. Previous history of allergy was a risk factor for NSAID hypersensitivity (p = 0.001). Vitamin D deficiency in the blood serum was a risk factor for NASID hypersensitivity (OR = 5.76 (95% Cl: 1.42-23.41)).

CONCLUSIONS

Hypersensitivity to NSAIDs is a difficult diagnostic problem in pediatric allergy. The most common manifestation of hypersensitivity to ibuprofen in children is acute urticaria and angioedema. Two important problems in the differential diagnosis are cofactors such as vitamin D levels and viral infections, which require further research.

How Infection and Vaccination Are Linked to Acute and Chronic Urticaria: A Special Focus on COVID-19

Since more than a century ago, there has been awareness of the connection between viral infections and the onset and exacerbation of urticaria. Our knowledge about the role of viral infection and vaccination in acute and chronic urticaria improved as a result of the COVID-19 pandemic but it has also highlighted knowledge gaps. Viral infections, especially respiratory tract infections like COVID-19, can trigger the onset of acute urticaria (AU) and the exacerbation of chronic urticaria (CU). Less frequently, vaccination against viruses including SARS-CoV-2 can also lead to new onset urticaria as well as worsening of CU in minority. Here, with a particular focus on COVID-19, we review what is known about the role of viral infections and vaccinations as triggers and causes of acute and chronic urticaria. We also discuss possible mechanistic pathways and outline the unmet needs in our knowledge. Although the underlying mechanisms are not clearly understood, it is believed that viral signals, medications, and stress can activate skin mast cells (MCs). Further studies are needed to fully understand the relevance of viral infections and vaccinations in acute and chronic urticaria and to better clarify causal pathways.

Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS): Focus on the Pathophysiological and Diagnostic Role of Viruses

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a heterogeneous, multiorgan and potentially life-threatening drug-hypersensitivity reaction (DHR) that occurs several days or weeks after drug initiation or discontinuation. DHRs constitute an emerging issue for public health, due to population aging, growing multi-organ morbidity, and subsequent enhanced drug prescriptions. DRESS has more consistently been associated with anticonvulsants, allopurinol and antibiotics, such as sulphonamides and vancomycin, although new drugs are increasingly reported as culprit agents. Reactivation of latent infectious agents such as viruses (especially Herpesviridae) plays a key role in prompting and sustaining aberrant T-cell and eosinophil responses to drugs and pathogens, ultimately causing organ damage. However, the boundaries of the impact of viral agents in the pathophysiology of DRESS are still ill-defined. Along with growing awareness of the multifaceted aspects of immune perturbation caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the ongoing SARS-CoV-2-related disease (COVID-19) pandemic, novel interest has been sparked towards DRESS and the potential interactions among antiviral and anti-drug inflammatory responses. In this review, we summarised the most recent evidence on pathophysiological mechanisms, diagnostic approaches, and clinical management of DRESS with the aim of increasing awareness on this syndrome and possibly suggesting clues for future research in this field.

Viral infections and drug hypersensitivity

Virus infections and T-cell-mediated drug hypersensitivity reactions (DHR) can influence each other. In most instances, systemic virus infections appear first. They may prime the reactivity to drugs in two ways: First, by virus-induced second signals: certain drugs like β-lactam antibiotics are haptens and covalently bind to various soluble and tissue proteins, thereby forming novel antigens. Under homeostatic conditions, these neo-antigens do not induce an immune reaction, probably because co-stimulation is missing. During a virus infection, the hapten-modified peptides are presented in an immune-stimulatory environment with co-stimulation. A drug-specific immune reaction may develop and manifest as exanthema. Second, by increased pharmacological interactions with immune receptors (p-i): drugs tend to bind to proteins and may even bind to immune receptors. Without viral infections, this low affine binding may be insufficient to elicit T-cell activation. During a viral infection, immune receptors are more abundantly expressed and allow more interactions to occur. This increases the overall avidity of p-i reactions and may even be sufficient for T-cell activation and symptoms. There is a situation where the virus-DHR sequence of events is inversed: in drug reaction with eosinophilia and systemic symptoms (DRESS), a severe DHR can precede reactivation and viremia of various herpes viruses. One could explain this phenomenon by the massive p-i mediated immune stimulation during acute DRESS, which coincidentally activates many herpes virus-specific T cells. Through p-i stimulation, they develop a cytotoxic activity by killing herpes peptide-expressing cells and releasing herpes viruses. These concepts could explain the often transient nature of DHR occurring during viral infections and the often asymptomatic herpes-virus viraemia after DRESS.

Incidence of Allergic Drug Eruption due to Cotrimoxazole in HIV-Positive Individuals with CD4 ≤200 Cells/ul

Allergic drug eruptions (ADE) remain a challenge in people living with HIV (PLWH), requiring more studies to guide clinical approaches. While cotrimoxazole is widely used as prophylaxis in PLWH, relationship between client characteristics toward the occurrence of cotrimoxazole ADEs is still poorly understood.A retrospective cohort study followed PLWH initiated with antiretroviral therapy (ART) in St. Carolus Hospital between January 2009 to December 2021. ADE occurrence due to cotrimoxazole were tested for significance using Pearson's Chi-square and Fisher's Exact Test (significant outcome measured as p < 0.05) against CD4 levels at very low (0-100 cells/ul) and low (101-200 cells/ul) groups, comorbidities, and retention status.Cotrimoxazole-related ADEs occurred in 258 (14%) of 1789 subjects with CD4 levels ≤200 cells/ul. Comorbidities of Hepatitis B, Hepatitis C, and M. tuberculosis infections were found in 11, 4, and 95 subjects respectively. 151 (59%) of ADE group had very low CD4 levels (p value > 0.05). No significant difference was found in ADE incidence between age groups, genders, CD4 levels, comorbidities, and ART retention.Cotrimoxazole-induced ADE is unrelated to CD4 levels, and ART retention was not affected. ADE severity ranges from mild to serious manifestations, and close monitoring is crucial to ensure ADEs are treated ART are well-maintained.

Tools to improve the diagnosis and management of T-cell mediated adverse drug reactions

Delayed drug T-cell immune-mediated hypersensitivity reactions have a large clinical heterogeneity varying from mild maculopapular exanthema (MPE) to severe cutaneous adverse reactions (SCARs) such as acute generalized exanthematous pustulosis (AGEP), drug reaction with eosinophilia and systemic symptoms (DRESS) and severe skin necrosis and blistering as seen in Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). Given the knowledge gaps related to the immunopathogenesis of these conditions, the absence of validated diagnostic tools and the significant associated morbidity and mortality, patients with SCARs often have limited drug choices. We performed a comprehensive review aiming to evaluate in vivo diagnostic tools such as delayed intradermal skin and patch testing and ex vivo/in vitro research assays such as the lymphocyte transformation test (LTT) and the enzyme-linked ImmunoSpot (ELISpot) assay. We searched through PubMed using the terms “drug allergy,” “in vivo” and “ex vivo” for original papers in the last 10 years. A detailed meticulous approach adapted to the various clinical phenotypes is recommended for the diagnostic and management of delayed drug hypersensitivity reactions. This review highlights the current diagnostic tools for the delayed drug hypersensitivity phenotypes.

Confirmation of Drug Allergy in a General Pediatrics Outpatient Clinic

BACKGROUND

The studies including diagnostic workup on true drug allergy in children are limited.

OBJECTIVE

This study aimed to evaluate the frequency of confirmed drug allergies in children with a history of suspected drug allergies who had applied to the general paediatric outpatient clinics of our hospital due to various health problems.

METHODS

The history of drug allergy was questioned in children who applied to the general pediatric outpatient clinics of our hospital. Allergy tests were performed to confirm drug allergy in children whose history was compatible with drug allergy.

RESULTS

In this study, the parents of 5,553 children aged between 4 months and 17.9 years were asked, "Has your child ever developed an allergy after drug use?". Seven percent of parents (n=389/5,553) thought that their child had a drug allergy. When these patients were evaluated by a paediatric allergist, it was suspected that 21.1% (n=82/389) had a drug allergy. When diagnostic tests were performed for drug allergies, drug allergy was confirmed in only 4.2% (n=3/72). As a result, the frequency of drug allergies according to the history was 1.47% (n=82/5,553) in the population we studied, while the frequency of confirmed drug allergies was found to be 0.05% (n=3/5,553).

CONCLUSION

The patient and/or parent statements alone are not sufficient for the diagnosis of drug allergies in children. In order to confirm or rule out drug allergies, drug allergy tests must be performed and so unnecessary drug restrictions can be avoided.

Multisystem Inflammatory Syndrome in Children: Examining Emerging Data and Identifying Key Knowledge Gaps

ABSTRACT

Multisystem inflammatory syndrome in children (MIS-C) is a syndrome of abnormal immune response after severe acute respiratory syndrome coronavirus 2 infection that can result in organ dysfunction including severe cardiovascular compromise in children. Increased evidence supports a clinical and laboratory profile in MIS-C distinct from Kawasaki disease, with MIS-C typically occurring in older children and with more prominent gastrointestinal and neurologic symptoms, as well as increased inflammation, lymphopenia, and cardiac injury on laboratory testing. However, high-level evidence regarding best practices for treatment and long-term outcomes in MIS-C is limited.

Type B adverse drug reactions to antibiotics and antibiotic allergy in infants and children

BACKGROUND

Distinguishing allergic reactions from non-allergic type B adverse drug reactions (ADRs) to antibiotics is challenging, particularly in children, because we lack epidemiological information that can be used in primary care situations. This study aimed to investigate the characteristics of type B ADRs to antibiotics and antibiotic allergy (AA) in previously healthy children.

METHODS

This was a retrospective cohort study of previously healthy children admitted for treating urinary tract infections over a 10 year period. The primary outcome was the frequency of type B ADRs and AAs that were assessed by pediatricians. Secondary outcomes include demographic data about patients' backgrounds, infections, treatments, ADRs, and action against ADRs. All the data were collected via patients' medical records.

RESULTS

Out of 791 participants, type B ADRs were reported in 77 children (9.7%), and AA labeling was performed in six children (0.8%). Physicians assessed 30.4% of type B ADRs as severe or life-threatening symptoms. All patients were discharged without long-term complications. Physicians detected the primary cause (individual patient host factors or environmental risks) in 39 cases of type B ADRs.

CONCLUSION

Type B ADRs to antibiotics were frequently reported even in previously healthy children. Physicians should use appropriate techniques (e.g., specialist consulting and skin testing) when they suspect that a type B ADR might be an AA. Labeling and de-labeling programs and tools for type B ADRs related to antibiotics should be implemented to prevent the mislabeling of AA.