HLA-B*07:02 and HLA-C*07:02 are associated with trimethoprim-sulfamethoxazole respiratory failure

Definition and Clinical Evaluation for Trimethoprim-Sulfamethoxazole Severe Acute Respiratory Failure

OBJECTIVES

Trimethoprim-sulfamethoxazole (TMP-SMX)-associated severe acute respiratory distress syndrome (ARDS) has gone underrecognized. We propose the first disease definition and clinical evaluation for a novel adverse drug reaction (ADR) based on a series of recently identified rare cases of life-threatening ADRs.

DESIGN

A retrospective study was conducted. All medical records were evaluated. Available pathology samples were sent to Massachusetts General for clinical consultation. Blood samples from surviving patients were obtained and human leukocyte antigen (HLA) analysis was performed by the Children's Mercy Hospital Genomic Center and Vanderbilt University Medical Center.

SETTING

U.S. ICUs, 1996-2021.

PATIENTS

Nineteen young patients (10-37) were identified. Patients were previously healthy, with no preexisting pulmonary disease, no other cause for respiratory failure, and no chronic history of smoking/vaping.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Through our retrospective analysis, we analyzed clinical characteristics associated with TMP-SMX. Pathology samples were reviewed, and HLA analysis was performed on available samples by the study team or as standard of care at treatment hospitals in some cases. In 19 critically ill patients, we identified a pattern of severe respiratory failure requiring ICU admission, mechanical ventilation, and frequent extracorporeal membrane oxygenation use. We describe the first three-part clinical diagnosis and evaluation strategy: 1) Clinical definition: Unexplained severe respiratory failure in a patient receiving greater than or equal to 6 days of TMP-SMX at treatment dose (not prophylaxis). TMP-SMX ARDS is a diagnosis of exclusion. 2) Genetic association: One hundred percent of currently available TMP-SMX respiratory failure patient genomic data, ( n = 11) have been carriers of both HLA-B*07:02 and HLA-C*07:02 alleles. HLA allele evaluation could be considered in patients with suspected TMP-SMX respiratory failure. 3) Lung pathology: A unique pulmonary pathologic pattern of lung injury termed diffuse alveolar injury with delayed epithelialization has been observed in these cases. In suspected cases, surgical lung biopsy early in the clinical course could be considered.

CONCLUSIONS

TMP-SMX is a commonly prescribed antibiotic. However, we find it imperative to share this relatively rare but life-threatening condition with clinicians as the mortality rate approaches 40%.

Trimethoprim-sulfamethoxazole-induced lung injury: a case report

Background

Trimethoprim-sulfamethoxazole (TMP-SMX) is a commonly used antibiotic. While cutaneous adverse drug reactions associated with TMP-SMX are commonly recognized, lung toxicity induced by TMP-SMX is an unusual condition, with scattered reports of hypersensitivity pneumonitis, acute fibrinous organizing pneumonia, interstitial lung disease and acute respiratory distress syndrome. Reports of TMP-SMX-associated drug-induced lung injury (DLI) are rare in the pediatric population and its pathogenesis is not well understood. Diagnosis of DLI remains a challenge, given the wide range of clinical presentations that overlap with other conditions and the lack of diagnostic tests. In this report, we describe a case of TMP-SMX-induced lung injury in an eight-year-old child.

Case Description

An eight-year-old girl presented in respiratory failure with acute symptoms of shortness of breath, fever, maculopapular rash and vomiting. This was associated with pneumonitis, pneumothorax, pneumomediastinum and subcutaneous emphysema on imaging. She had been on 25 days of TMP-SMX for treatment of Group D Salmonella bacteremia and osteomyelitis that was diagnosed prior to this current presentation. TMP-SMX was discontinued on admission due to concerns of possible drug reaction. Extensive infective, autoimmune and immunologic workup did not reveal the cause of the respiratory failure. Considering the absence of an alternative explanation for her clinical presentation and similarities in clinical courses to other reported cases, she was eventually diagnosed with TMP-SMX-associated DLI. She received a course of corticosteroids with subsequent clinical improvement and was weaned off home oxygen therapy a few months after her discharge from the hospital.

Conclusions

Diagnosis of DLI can be challenging. The early identification of DLI and discontinuation of culprit drug is essential in its management. Further understanding of the underlying pathophysiology and risk factors for TMP-SMX-associated DLI is required.

"HLA-C: evolution, epigenetics, and pathological implications in the major histocompatibility complex"

HLA-C, a gene located within the major histocompatibility complex, has emerged as a prominent target in biomedical research due to its involvement in various diseases, including cancer and autoimmune disorders; even though its recent addition to the MHC, the interaction between HLA-C and KIR is crucial for immune responses, particularly in viral infections. This review provides an overview of the structure, origin, function, and pathological implications of HLA-C in the major histocompatibility complex. In the last decade, we systematically reviewed original publications from Pubmed, ScienceDirect, Scopus, and Google Scholar. Our findings reveal that genetic variations in HLA-C can determine susceptibility or resistance to certain diseases. However, the first four exons of HLA-C are particularly susceptible to epigenetic modifications, which can lead to gene silencing and alterations in immune function. These alterations can manifest in diseases such as alopecia areata and psoriasis and can also impact susceptibility to cancer and the effectiveness of cancer treatments. By comprehending the intricate interplay between genetic and epigenetic factors that regulate HLA-C expression, researchers may develop novel strategies for preventing and treating diseases associated with HLA-C dysregulation.

Novel Fab-peptide-HLA-I fusion proteins for redirecting pre-existing anti-CMV T cell immunity to selective eliminate carcinoma cells

Typically, anticancer CD8pos T cells occur at low frequencies and become increasingly impaired in the tumor micro environment. In contrast, antiviral CD8pos T cells display a much higher polyclonality, frequency, and functionality. In particular, cytomegalovirus (CMV) infection induces high numbers of 'inflationary' CD8pos T cells that remain lifelong abundantly present in CMV-seropositive subjects. Importantly, these so-called inflationary anti-CMV T cells increase with age, maintain a ready-to-go state, populate tumors, and do not become exhausted or senescent. Given these favorable attributes, we devised a novel series of recombinant Fab-peptide-HLA-I fusion proteins and coined them 'ReTARGs'. A ReTARG fusion protein consists of a high-affinity Fab antibody fragment directed to carcinoma-associated cell surface antigen EpCAM (or EGFR), fused in tandem with soluble HLA-I molecule/β2-microglobulin, genetically equipped with an immunodominant peptide derived from CMV proteins pp65 (or IE-1). Decoration with EpCAM-ReTARGpp65 rendered EpCAM-expressing primary patient-derived carcinoma cells highly sensitive to selective elimination by cognate anti-CMV CD8pos T cells. Importantly, this treatment did not induce excessive levels of proinflammatory T cell-secreted IFNγ. In contrast, analogous treatment with equimolar amounts of EpCAM/CD3-directed bispecific T-cell engager solitomab resulted in a massive release of IFNγ, a feature commonly associated with adverse cytokine-release syndrome. Combinatorial treatment with EpCAM-ReTARGpp65 and EGFR-ReTARGIE-1 strongly potentiated selective cancer cell elimination owing to the concerted action of the corresponding cognate anti-CMV CD8pos T cell clones. In conclusion, ReTARG fusion proteins may be useful as an alternative or complementary form of targeted cancer immunotherapy for 'cold' solid cancers.