Cutaneous legionellosis: case report and review of the medical literature

Bacterial Pathogens Causing Pneumonia Post Hematopoietic Stem Cell Transplant: The Chronic GVHD Population

Allogeneic stem cell transplantation is a lifesaving treatment for many malignancies. Post-transplant patients may suffer from graft versus host disease in the acute and/or the chronic form(s). Post-transplantation immune deficiency due to a variety of factors is a major cause of morbidity and mortality. Furthermore, immunosuppression can lead to alterations in host factors that predisposes these patients to infections. Although patients who receive stem cell transplant are at an increased risk of opportunistic pathogens, which include fungi and viruses, bacterial infections remain the most common cause of morbidity. Here, we review bacterial pathogens that lead to pneumonias specifically in the chronic GVHD population.

Legionella longbeachae wound infection: case report and review of reported Legionella wound infections

Extrapulmonary manifestations of infection with Legionella species, of which 24 may cause disease in humans, are very rare. Here, we describe a case of a 61-year-old woman with no history of immunosuppression presenting with pain and swelling of her index finger after a prick by rose thorns during gardening. Clinical examination showed fusiform swelling of the finger with mild redness, warmth, and fever. The blood sample revealed a normal white blood cell count and a slight increase in C-reactive protein. Intraoperative observation showed extensive infectious destruction of the tendon sheath, while the flexor tendons were spared. Conventional cultures were negative, while 16S rRNA PCR analysis identified Legionella longbeachae that also could be isolated on buffered charcoal yeast extract media. The patient was treated with oral levofloxacin for 13 days, and the infection healed quickly. The present case report, with a review of the literature, indicates that Legionella species wound infections may be underdiagnosed due to the requirement for specific media and diagnostic methods. It emphasizes the need for heightened awareness of these infections during history taking and clinical examination of patients presenting with cutaneous infections.

A case of disseminated Legionnaires’ disease: The value of metagenome next-generation sequencing in the diagnosis of Legionnaires

Background

Legionella rarely causes hospital-acquired pneumonia (HAP), although it is one of the most common pathogens of community-acquired pneumonia. Hospital-acquired Legionnaires’ disease, mainly occurring in immunocompromised patients, is often delayed in diagnosis with high mortality. The use of the metagenome Next-Generation Sequencing (mNGS) method, which is fast and unbiased, allows for the early detection and identification of microorganisms using a culture-independent strategy.

Case report

A 52-year-old male, with a past medical history of Goods syndrome, was admitted due to nephrotic syndrome. The patient developed severe pneumonia, rhabdomyolysis, and soft tissue infection after receiving immunosuppressive therapy. He did not respond well to empiric antibiotics and was eventually transferred to the medical intensive care unit because of an acute respiratory failure and septic shock. The patient then underwent a comprehensive conventional microbiological screening in bronchoalveolar lavage fluid (BALF) and blood, and the results were all negative. As a last resort, mNGS of blood was performed. Extracellular cell-free and intracellular DNA fragments of Legionella were detected in plasma and blood cell layer by mNGS, respectively. Subsequent positive results of polymerase chain reaction for Legionella in BALF and soft tissue specimens confirmed the diagnosis of disseminated Legionnaires’ disease involving the lungs, soft tissue, and blood stream. The patient’s condition improved promptly after a combination therapy of azithromycin and moxifloxacin. He was soon extubated and discharged from ICU with good recovery.

Conclusion

Early recognition and diagnosis of disseminated Legionnaires’ disease is challenging. The emergence and innovation of mNGS of blood has the potential to address this difficult clinical issue.

Legionnaires' disease presenting with exanthem; Case and review of previously published cases

Infection with Legionella spp. (legionellosis) causes two distinct clinical presentations: Legionnaires’ Disease and Pontiac Fever. Legionnaire’s Disease primarily involves the lungs, often with accompanying gastrointestinal symptoms, and can also affect the liver, central nervous system, and kidneys, and cause metabolic derangements. Manifestations in the integumentary system are rare; to date, there have been eleven cases reported in the literature of Legionellosis with associated rash, with varied presentation. The relationship between Legionella pneumophila and the skin has not yet been clearly defined; immunological and/or toxic pathogenesis are possible. We report a case of Legionnaires’ Disease in a young immunocompromised man with a largely benign clinical course consisting of predominantly gastrointestinal symptoms and an extensive maculopapular rash. Chest radiography showed lobar infiltrate in the absence of clinical symptoms of pneumonia. The importance of this case is for clinicians to maintain high clinical suspicion for Legionella when extra-pulmonary symptoms predominate, specifically in immunocompromised hosts who may have atypical presentations and have higher mortality rates when treatment is delayed.

Multidisciplinary Management of Legionella Disease in Immunocompromised Patients

Legionella pneumonia is a gram-negative bacterial infection commonly associated with aerosol transmission from contaminated water sources. Impaired immunity leads to delayed clearance of infection and further predisposes individuals with Legionella pneumonia at risk of developing complications. We present a case report on a renal transplant patient with comorbid cardiac and renal dysfunction who developed community-acquired Legionella pneumonia. The case emphasizes the importance of adopting a multidisciplinary approach when managing Legionella infection in patients with multiple comorbidities and immunosuppressive states.

Severe Pneumonia in Neonates Associated with Legionella pneumophila: Case Report and Review of the Literature

The causative agent of legionellosis is the Gram-negative intracellular bacteria Legionella spp. Its clinical presentation varies from a mild febrile illness called Pontiac fever to the severe and possible fatal pneumonia, Legionnaires’ disease. Immunocompromised patients, in particular, are affected. Only a small number of infected neonates are described in the literature. Most of them have been associated with water birth or the use of air humidifiers. In the last five years, a growing number of cases have been reported in Germany by the national institute of disease surveillance and prevention (Robert-Koch Institute). Here, we describe a fatal case report of pulmonary legionellosis with acute respiratory distress syndrome (ARDS), sepsis, associated cutaneous manifestation, and extracorporeal membrane oxygenation in a full-term neonate. Moreover, we present a review of the literature discussing the epidemiology, risk factors, clinical features, diagnostics, treatment options, and prevention for this rare condition in neonates.

Hypertriglyceridemia and massive rhabdomyolysis in a patient with disseminated legionella

Legionella most commonly presents as pneumonia but can have disseminated involvement, presenting as extra-pulmonary disease involving gastrointestinal, neurological, cardiac, renal, and musculoskeletal systems, and skin and soft tissues. We present a case of a patient with pneumonia, rhabdomyolysis, renal failure, hypertriglyceridemia, pancreatitis, and cutaneous involvement. This case highlights the breath of involvement legionella can have, including the never previously documented manifestation of hypertriglyceridemia and severe rhabdomyolysis with the highest creatinine kinase recorded.

The clinical presentation of Legionella arthritis reveals the mode of infection and the bacterial species: case report and literature review

BACKGROUND

While Legionella is a common cause of pneumonia, extrapulmonary infections like arthritis are scarce. Here, we describe a case of monoarthritis due to Legionella bozemanii, with no history of pneumonia. We provide a literature review of the 9 previously published Legionella arthritis and highlight a dichotomous epidemiology suggesting different physiopathological pathways leading to joint infection.

CASE PRESENTATION

A 56-year old woman under immunosuppressive treatment by oral and intra-articular corticosteroids, methotrexate, and tocilizumab for an anti-synthetase syndrome was hospitalized for worsening pain and swelling of the left wrist for 3 days. Clinical examination showed left wrist synovitis and no fever. The arthritis occurred a few days after an accidental fall on wet asphalt responsible for a cutaneous wound followed by a corticosteroid intra-articular injection. Due to both the negativity of conventional culture of articular fluid and suspicion of infection, 16S rRNA and specific PCRs were performed leading to the identification of L. bozemanii. Legionella-specific culture of the articular fluid was performed retrospectively and isolated L. bozemanii. The empiric antibiotic therapy was switched for oral levofloxacin and rifampin and the patient recovered after a 12-week treatment.

CONCLUSION

We report a case of L. bozemanii monoarthritis in an immunosuppressed woman, following a fall on wet asphalt and intra-articular corticosteroid injection. The review of the literature found that the clinical presentation reveals the mode of infection and the bacterial species. Monoarthritis more likely occurred after inoculation in patients under immunosuppressive therapy and were associated with non-Legionella pneumophila serogroup 1 (Lp1) strains that predominate in the environment. Polyarthritis were more likely secondary legionellosis localizations after blood spread of Lp1, the most frequently found in pneumonia. In both settings, 16S rRNA and Legionella-specific PCR were key factors for the diagnosis.

Disseminated extrapulmonary Legionella pneumophila infection presenting with panniculitis: case report and literature review

BACKGROUND

Legionellosis is a well-known cause of pneumonia. Primary cutaneous and subcutaneous infection caused by Legionella pneumophila is rare and the diagnosis is challenging.

CASE PRESENTATION

A 38-year-old Thai woman with systemic lupus erythematosus and myasthenia gravis treated with prednisolone and azathioprine presented to our hospital with low-grade fever, diarrhea, and indurated skin lesions on both thighs. Initial examination showed plaques on both inner thighs. Magnetic resonance imaging showed myositis and swelling of the skin and subcutaneous tissue. Diagnosis of panniculitis due to L. pneumophila was carried out by histopathology, Gram stain, and 16S rRNA gene sequencing method of tissue biopsy from multiple sites on both thighs. Myocarditis was diagnosed by echocardiography. The final diagnosis was disseminated extrapulmonary legionellosis. Treatment comprised intravenous azithromycin for 3 weeks and the skin lesions, myositis and myocarditis resolved. Oral azithromycin and ciprofloxacin were continued for 3 months to ensure eradication of the organism. The patient's overall condition improved.

CONCLUSIONS

To our knowledge, we report the first case of L. pneumophila infection manifesting with panniculitis, possible myositis, and myocarditis in the absence of pneumonia. The diagnosis of extrapulmonary Legionella infection is difficult, especially in the absence of pneumonia. A high index of suspicion and appropriate culture with special media or molecular testing are required. Initiation of appropriate treatment is critical because delaying therapy was associated with progressive infection in our patient.

Ten Questions Concerning the Aerosolization and Transmission of Legionella in the Built Environment

Legionella is a genus of pathogenic Gram-negative bacteria responsible for a serious disease known as legionellosis, which is transmitted via inhalation of this pathogen in aerosol form. There are two forms of legionellosis: Legionnaires' disease, which causes pneumonia-like symptoms, and Pontiac fever, which causes influenza-like symptoms. Legionella can be aerosolized from various water sources in the built environment including showers, faucets, hot tubs/swimming pools, cooling towers, and fountains. Incidence of the disease is higher in the summertime, possibly because of increased use of cooling towers for air conditioning systems and differences in water chemistry when outdoor temperatures are higher. Although there have been decades of research related to Legionella transmission, many knowledge gaps remain. While conventional wisdom suggests that showering is an important source of exposure in buildings, existing measurements do not provide strong support for this idea. There has been limited research on the potential for Legionella transmission through heating, ventilation, and air conditioning (HVAC) systems. Epidemiological data suggest a large proportion of legionellosis cases go unreported, as most people who are infected do not seek medical attention. Additionally, controlled laboratory studies examining water-to-air transfer and source tracking are still needed. Herein, we discuss ten questions that spotlight current knowledge about Legionella transmission in the built environment, engineering controls that might prevent future disease outbreaks, and future research that is needed to advance understanding of transmission and control of legionellosis.

Legionnaires' disease in transplant recipients: A 15-year retrospective study in a tertiary referral center

Legionnaires' disease (LD) can be fatal among high-risk transplant recipients. To understand the epidemiology of LD, we reviewed 15-year longitudinal data from a center in Seattle, Washington that cares for both solid organ transplant (SOT) and hematopoietic cell transplant (HCT) recipients. We identified all laboratory-confirmed LD and extracted data on species, diagnostic modalities, clinical presentation, management, and outcomes from medical records. Among 32 patients with LD, transplant recipients made up the majority of diagnoses (22, 69%; SOT 10, HCT 12). Approximately 0.8% of transplant recipients who underwent Legionella-specific testing were positive. Non-pneumophila Legionella species (LNLP), which are not detected by urinary antigen test, accounted for half the cases, led by Legionella micdadei (32%). The severity and outcome between Legionella pneumophila and LNLP infections were similar (attributed mortality, 36% vs 27%); all LNLP deaths occurred in transplant recipients with L. micdadei. The clinical and radiological features mimicked other opportunistic pathogens; 32% (n=7) were not on empiric treatment at the time of diagnosis. These data add to the emerging literature describing the importance of LD and highlight the need for both routine Legionella testing on transplant recipients with pulmonary findings and empiric Legionella-active antibiotic therapy.

Skin and Soft Tissue Infections

The skin is colonized by a diverse collection of microorganisms which, for the most part, peacefully coexist with their hosts. Skin and soft tissue infections (SSTIs) encompass a variety of conditions; in immunocompromised hosts, SSTIs can be caused by diverse microorganisms-most commonly bacteria, but also fungi, viruses, mycobacteria, and protozoa. The diagnosis of SSTIs is difficult because they may commonly masquerade as other clinical syndromes or can be a manifestation of systemic disease. In immunocompromised hosts, SSTI poses a major diagnostic challenge, and clinical dermatological assessment should be initially performed; to better identify the pathogen and to lead to appropriate treatment, etiology should include cultures of lesions and blood, biopsy with histology, specific microbiological analysis with special stains, molecular techniques, and antigen-detection methodologies. Here, we reviewed the epidemiology, pathophysiology, clinical presentation, and diagnostic techniques, including molecular biological techniques, used for SSTIs, with a focus on the immunocompromised host, such as patients with cellular immunodeficiency, HIV, and diabetic foot infection.

Cutaneous Legionella longbeachae Infection in Immunosuppressed Woman, United Kingdom

We report a rare case of cutaneous Legionella longbeachae infection in a patient receiving long-term corticosteroids for immune thrombocytopenia. Such infections cannot be identified by using Legionella urinary antigen testing but are commonly seen after exposure to commercial potting compost, particularly in immunocompromised patients.

Legionellosis in Transplantation

Legionella species are emerging opportunistic pathogens in hematopoietic stem cell and solid organ transplant recipients, associated with significant morbidity and mortality. The clinical and radiological features of Legionella infections can mimic other opportunistic pathogens in these profoundly immunocompromised patients. Diagnosis in transplant patients is challenging as non-pneumophila Legionella infections, for which these patients are at risk, cannot be identified using the urinary antigen test. Changes in management of transplant recipients and changes in Legionella epidemiology suggest that the number of transplant patients potentially exposed to Legionella spp. may be on the rise. Yet, evidence-based, transplant-specific guidelines for managing and preventing Legionella infections are not currently available. In this article, we review the epidemiology, clinical features, diagnostic challenges, treatment options, and preventive strategies of Legionella infections in these high-risk patient populations.

Compost and Legionella longbeachae: an emerging infection?

Human disease caused by Legionella species is dominated by Legionella pneumophila, the main causative agent in cases of Legionnaires’ disease. However, other species are known to cause infection, for example, Legionella longbeachae causes an equivalent number of cases of disease as L. pneumophila in Australia and New Zealand. Infection with L. longbeachae is commonly associated with exposure to composts and potting soils, and cases of infection with this organism have been increasing in Europe over the past ten years. The increase in incidence may be linked to factors such as increased awareness of clinical presentation, or due to changing formulation of growing media, although it should be noted that the presence of Legionella species in growing media does not correlate with the number of cases currently seen. This is likely due to the variables associated with infection, for example, host factors such as smoking or underlying health conditions, or difference in growing media storage or climate, especially warm humid conditions, which may affect survival and growth of these organisms in the growing media environment. There are numerous unknowns in this area and collaboration between growing media manufacturers and researchers, as well as more awareness among diagnosing clinicians, laboratory staff and the general public is necessary to reduce risk. More research is needed before definitive conclusions can be drawn: L. pneumophila research currently dominates the field and it is likely that the overreliance on diagnostic techniques such as the urinary antigen test, which is specific for L. pneumophila Sg 1, is detrimental to the diagnosis of L. longbeachae infection.

Isolation on Chocolate Agar Culture of Legionella pneumophila Isolates from Subcutaneous Abscesses in an Immunocompromised Patient

Cutaneous infections due to Legionella species have rarely been reported (L. J. Padrnos, J. E. Blair, S. Kusne, D. J. DiCaudo, and J. R. Mikhael, Transpl Infect Dis 16:307-314, 2014; P. W. Lowry, R. J. Blankenship, W. Gridley, N. J. Troup, and L. S. Tompkins, N Engl J Med 324:109-113, 1991; M. K. Waldor, B. Wilson, and M. Swartz, Clin Infect Dis 16:51-53, 1993). Here we report the identification of Legionella pneumophila isolates, from subcutaneous abscesses in an immunocompromised patient, that grew in an unusual medium for Legionella bacteria.