Achromobacter is a genus of nonfermenting Gram-negative bacteria under order Burkholderiales . Although primarily isolated from respiratory tract of people with cystic fibrosis, Achromobacter spp. can cause a broad range of infections in hosts with other underlying conditions. Their rare occurrence and ever-changing taxonomy hinder defining their clinical features, risk factors for acquisition and adverse outcomes, and optimal treatment. Achromobacter spp.

Carbapenemase-producing Enterobacteriaceae (CPE) contribute significantly to the global public health threat of antimicrobial resistance. OXA-48 and its variants are unique carbapenemases with low-level hydrolytic activity toward carbapenems but no intrinsic activity against expanded-spectrum cephalosporins. bla_OXA-48 is typically located on a plasmid but may also be integrated chromosomally, and this gene has progressively disseminated throughout Europe and the Middle East. Despite the inability of OXA-48-like carbapenemases to hydrolyze expanded-spectrum cephalosporins, pooled isolates demonstrate high variable resistance to ceftazidime and cefepime, likely representing high rates of extended-spectrum beta-lactamase (ESBL) coproduction. In vitro data from pooled studies suggest that avibactam is the most potent beta-lactamase inhibitor when combined with ceftazidime, cefepime, aztreonam, meropenem, or imipenem. Resistance to novel avibactam combinations such as imipenem-avibactam or aztreonam-avibactam has not yet been reported in OXA-48 producers, although only a few clinical isolates have been tested. Although combination therapy is thought to improve the chances of clinical cure and survival in CPE infection, successful outcomes were seen in ∼70% of patients with infections caused by OXA-48-producing Enterobacteriaceae treated with ceftazidime-avibactam monotherapy. A carbapenem in combination with either amikacin or colistin has achieved treatment success in a few case reports. Uncertainty remains regarding the best treatment options and strategies for managing these infections. Newly available antibiotics such as ceftazidime-avibactam show promise; however, recent reports of resistance are concerning. Newer choices of antimicrobial agents will likely be required to combat this problem.

Rickettsia species causing human illness are present globally and can cause significant disease. Diagnosis and identification of this intracellular bacteria are challenging with many available diagnostic modalities suffering from several shortcomings. Detection of antibodies directed against Rickettsia spp. via serological methods remains widely used with a broad range of sensitivity and specificity values reported depending on the assay. Molecular methods, including polymerase chain reaction (PCR) testing, enables species-specific identification with a fast turnaround time; however, due to resource requirements, use in some endemic settings is limited. Reports on the use of next-generation sequencing (NGS) and metagenomics to diagnose Rickettsia spp. infection have been increasing. Despite offering several potential advantages in the diagnosis and surveillance of disease, genomic approaches are currently only limited to reference and research laboratories. Continued development of Rickettsia spp. diagnostics is required to improve disease detection and epidemiological surveillance, and to better understand transmission dynamics.

Chimeric antigen receptor (CAR) T-cell therapy is a revolutionary treatment modality used to treat haematological malignancies. Lymphocytes are engineered to produce CARs directed towards tumour cell antigens. Clinical trials have demonstrated impressive malignancy-related outcomes. Unfortunately, numerous off-target effects can cause toxicity-related adverse events in this population, the main being cytokine release syndrome and immune effector cell neurotoxicity syndrome. This causes significant patient morbidity and poor outcomes. Patients who receive CAR T-cell therapy are also profoundly immunosuppressed and often cytopenic, which is caused by a multitude of patient- and treatment-related factors. Thus, infection-related complications are also common in this group. Indeed, up to one third of patients will suffer a serious bacterial infection in the first 30 days after therapy. Viral respiratory tract infection appears to be the most common during the late phase and can be severe; one patient has died of influenza A infection. Fungal infection and cytomegalovirus (CMV) reactivation appear to be uncommon. Although institutional guidelines on infection-prevention strategies are available, there is a dearth of evidence to support their approach. Future research needs to target important unanswered questions that remain in this patient population in order to improve their short- and long-term outcomes.

Background: COVID‐19 is known to cause an acute respiratory illness, although clinical manifestations outside of the respiratory tract may occur. Early reports have identified SARS‐CoV‐2 as a cause of subacute thyroiditis (SAT).Methods: A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines. MEDLINE, Web of Science and PubMed databases were queried in February 2021 for studies from December 2019 to February 2021. MeSH search terms ‘COVID‐19’, ‘SARS‐CoV‐2’ and ‘coronavirus’ along with search terms ‘thyroiditis’, ‘thyrotoxicosis’ and ‘thyroid’ were used. Descriptive statistics for continuous variables and proportions for categorical variables were calculated.Results: Fifteen publications reporting on 17 individual cases of COVID‐19‐induced SAT were identified. Age ranged from 18 to 69 years. The majority (14 of 17; 82%) of cases were female. The delay between onset of respiratory symptoms and diagnosis of SAT ranged from 5 to 49 days (mean, 26.5). Systemic inflammatory response syndrome related to viral infection was uncommonly reported at the time of SAT diagnosis. Thyroid ultrasonography frequently reported an enlarged hypoechoic thyroid with decreased vascularity and heterogenous echotexture. Elevated C‐reactive protein (CRP) was common at the time of SAT diagnosis, with results ranging from 4.5 to 176 mg/L (mean, 41 mg/L). Antithyroid antibodies were frequently negative. SAT‐specific treatment included corticosteroids for 12 of 17 (70.5%) patients. Most returned to normal thyroid status.Conclusion: COVID‐19‐associated SAT may be difficult to identify in a timely manner due to potential absence of classic symptoms, as well as cross‐over of common clinical features between COVID‐19 and thyrotoxicosis.

Nosocomial clusters of fungal infections, whilst uncommon, cannot be predicted and are associated with significant morbidity and mortality. Here, we review reports of nosocomial outbreaks of invasive fungal disease to glean insight into their epidemiology, risks for infection, methods employed in outbreak detection including genomic testing to confirm the outbreak, and approaches to clinical and infection control management. Both yeasts and filamentous fungi cause outbreaks, with each having general and specific risks. The early detection and confirmation of the outbreak are essential for diagnosis, treatment of affected patients, and termination of the outbreak. Environmental sampling, including the air in mould outbreaks, for the pathogen may be indicated. The genetic analysis of epidemiologically linked isolates is strongly recommended through a sufficiently discriminatory approach such as whole genome sequencing or a method that is acceptably discriminatory for that pathogen. An analysis of both linked isolates and epidemiologically unrelated strains is required to enable genetic similarity comparisons. The management of the outbreak encompasses input from a multi-disciplinary team with epidemiological investigation and infection control measures, including screening for additional cases, patient cohorting, and strict hygiene and cleaning procedures. Automated methods for fungal infection surveillance would greatly aid earlier outbreak detection and should be a focus of research.