Legionella lymphadenitis in immunocompetent adult: Case report

Abstract

Introduction

Extrapulmonary legionella disease is rare and occasionally reported in immunocompromised patients; it includes lymphadenitis, panniculitis, hepatitis, atrio-ventricular block, arthritis, prosthetic valve endocarditis and myocarditis. In this article, we report a rare case of legionella suppurative lymphadenitis in an immunocompetent patient.

Case

53-year-old female patient from the Philippines, non-smoker, previously healthy who presented to our facility for chills and respiratory distress following a course of corticosteroid intake. She was admitted for respiratory failure and septic shock, and was diagnosed with legionella infection associated with extrapulmonary dissemination (lymphadenitis) leading to her death 72 h after admission.

Discussion

Legionella is an important cause of community acquired pneumonia (CAP) and a delay in appropriate antibiotic therapy was associated with an increased mortality rate. Since legionnaire’s disease is indistinguishable from other forms of pneumonia without diagnostic testing, empiric antibiotic therapy regimen should cover legionella species. In unfortunate cases, a delay in the diagnosis and treatment may lead to extrapulmonary manifestations such as lymphadenitis and will be associated with worse patient outcomes.

Conclusion

Legionella is an important cause of community acquired pneumonia which if left untreated can become complicated with extrapulmonary manifestations such as lymphadenitis and become eventually fatal to patients. A prompt early diagnosis and appropriate antimicrobial therapy covering legionella should be considered whenever treating community acquired pneumonia.

Introduction

Legionellosis is the term that encompasses all diseases caused by the Legionella bacteria, which is a gram-negative bacillus with fastidious growth requirements [1]. This disease is commonly caused by exposure to contaminated lakes, rivers, creeks, hot springs and other water sources. It varies in severity from a mild febrile illness to a serious and sometimes fatal form of pneumonia. The most common cause of illness is the freshwater species L. pneumophila, which is found in natural aquatic environments worldwide [2]. Extrapulmonary legionella disease is rare and is occasionally reported in immunocompromised patients. It includes lymphadenitis [3], [4], panniculitis [5], hepatitis [6], atrio-ventricular block [7], arthritis [8], prosthetic valve endocarditis [9] and myocarditis [10]. In this article, we report a rare case of legionella suppurative lymphadenitis in an immunocompetent patient.

Case

This is a case of a 53-year-old female patient from the Philippines, non-smoker, previously healthy who presented to our facility for chills and respiratory distress following a course of corticosteroid intake.

Her history goes back to 6 months prior to presentation when the patient started reporting dry cough soon after returning to Lebanon from her home country of Philippines. Her symptoms started to progress with the addition of a new onset fatigue and malaise. Otherwise review of systems was negative; no fever, gastro-intestinal symptoms or weight loss. She was seen by a primary care physician 1 month prior to presentation. As reported by the family, he noted the presence of right sided lymphadenopathy over the lower neck. Blood tests were ordered and showed a hemoglobin Drop to 8 g/dL from a baseline of 12 g/dL. PET scan was also done as outpatient and showed FDG uptake in the Supra and Infra diaphragmatic lymph nodes (mediastinal and abdominal), in addition to diffuse uptake in the spleen and bone marrow. To our knowledge, workup for chronic infections including tuberculosis, human immunodeficiency virus (HIV), hepatitis B/C as well as autoimmue disease was not performed at the time. Thus, a right cervical lymph node biopsy was done with a differential diagnosis including malignancy. After the biopsy, the patient was started on oral prednisone 50 mg daily pending pathology result.

One week later, the patient presented to the emergency department of our institution with respiratory distress. Upon presentation, the patient had a blood pressure of 125/75 mmHg, an oxygen saturation of 86 %, a heart rate of 130 beats per minute, a temperature of 37.5 degree Celsius and a respiratory rate of 22 per minute. Physical exam showed a clean biopsy wound; no other lymphadenopathy was noted; lung auscultation revealed decrease air entry over bilateral lower lung lobes without the presence of any adventitious sounds. Blood tests results are reported as seen in Table 1; they include a white blood cell count 36.5 × 10^3ul, a C-reactive protein CRP of 412 mg/L, a hemoglobin of 8.6 g/dL, a platelet count of 23 × 10^3ul and a D-dimer of 1285 ng/ml. Furthermore, CT scan of the chest showed the presence of the previously reported lymphadenopathies, in addition to a new onset of large right sided loculated pleural effusion with total collapse of right lung as seen in Figs. 1 and 2. Blood, urine and sputum cultures were taken. Trans thoracic echocardiography was normal. Patient was started on broad-spectrum intravenous IV antibiotics; meropenem 1 g every 8 h, levofloxacin 750 mg daily and vancomycin 1 g every 12 h. The patient received the transfusion of 1 unit of packed red blood cell and 2 pools of platelets and was transferred to the ICU. 24 h post admission oxygen requirements started to increase and her blood pressure started to decrease, so she was placed on mechanical ventilation and on pressors respectively. Deep tracheal aspirate (DTA) taken was negative for Acid Fast Bacilli (AFB) on preformed smear. During the same day, preliminary lymph node biopsy result suggested the presence of bacterial lymphadenitis. CT guided pleural drainage was negative for AFB and showed a lactate dehydrogenase LDH of 963 IU/L, a protein of 51 g/l, cell count of 337 white blood cells with a differential of 80 % neutrophils. Moreover, bronchoscopy was done and a broncho-alveolar lavage (BAL) was taken.

Table 1.

Laboratory investigations results progression during hospitalization.

	Upon admission	Day 1	Day 2	Day 3
WBC (x10^3ul)	36.5	25.5	22.6	29.7
Neutrophils (%)	94.1	96	93	93
Lymphocytes (%)	4.5	2.9	5	6.2
Hemoglobin (g/dl)	8.3	8.9	8.3	8.0
Platelets (x10^3ul)	23	64	65	50
Creatinine (mg/dl)	0.50	0.58	0.8	1.62
Sodium (mmol/L)	140	144	142	146
Potassium(mmol/L)	4.2	3.9	4.1	4.8
Chloride (mmol/L)	104	106	108	109
CO2 (mmol/L)	22	22	20	17
Fibrinogen (mg/dl)	662
D-dimer (ng/ml)	1285
CRP (mg/L)	412	410	472
INR	1.35	1.50	1.50	2.07
Troponin (ng/ml)	0.012	0.014	0.138
Triglyceride(mg/dL)		176
LDH (IU/L)	203	283	484
Pro-BNP (pg/ml)	736
Albumin (g/l)	25		20
Ferritin (ng/ml)		> 1675
Complement C3 (g/l)		1.20
Complement C4 (g/l)		0.54

Fig. 1.

Screenshot from CT scan of the chest, showing large right sided loculated pleural effusion reaching the apex associated with almost total consolidation collapse of the right lung.

Fig. 2.

screenshot from PET scan, showing multiple FDG avid enlarged lymph nodes in the bilateral lower cervical and supraclavicular areas, reaching up to 1.5 cm.

48 h post admission, the patient remained in respiratory distress with increased oxygen requirements due to complete right sided lung collapse, therefore the cardiothoracic surgery team was consulted and they decided to proceed with urgent lifesaving thoracotomy. In addition, caspofungin was added to her regimen to empirically cover for fungal infections. Bacterial respiratory polymerase chain reaction (PCR) panel taken from Broncho-alveolar lavage (BAL) was positive for Legionella spp. HIV testing and purified protein derivative (PPD) skin testing both were negative.

Despite application of appropriate medical and surgical management, the patient had a cardiopulmonary arrest during the third day after admission. Cardiopulmonary resuscitation was done without success. The patient was therefore pronounced dead due to fulminant Legionellosis.

To note, final pathology report stated the presence of reactive hemophagocytosis with overall pattern consistent with bacterial lymphadenitis; no evidence of malignancy was noted (including negative immunolabeling for Reed-Sternberg cells). Other pending investigations including BAL sample testing for tuberculosis (PCR and culture) as well as blood and urine cultures were all negative for any organisms including bacteria as well as fungi.

Discussion

Legionella infection is usually transmitted from the environment to humans by inhalation of an infectious aerosol. The bacterium L. pneumophila was first identified in 1977 as the cause of an outbreak of severe pneumonia in a convention center in the USA secondary to a poorly maintained artificial water systems [2].

Extrapulmonary legionella infections are rare. Metastatic infections have been reported almost exclusively in immunocompromised patients, or in patients with fatal Legionnaires’ Disease (LD), who may develop abscesses or extrapulmonary infections of the brain, spleen, lymph nodes, bones and myocardial muscles. Many sites of metastatic infection have been described including the intestines, liver, kidneys, peritoneum, pericardium, vascular shunts and grafts, bone marrow, joints, surgical wounds (including those related to prosthetic heart valves and the aorta), native heart valves, perinium, along with the skin and subcutaneous tissues [1].

To note, our patient, was not an elderly, nor did she have any past medical history that could contribute to this fatal presentation. She did not note any high-risk exposures during her stay, yet legionella is an important cause of atypical pneumonia in Philippines [11], [12]. In this paper, we are reporting a case of legionella lymphadenitis in an immunocompetent patient which has been reported only in a few cases in the literature [3], [4].

Legionella is an important cause of community acquired pneumonia (CAP) and a delay in appropriate antibiotic therapy was associated with an increased mortality rate [13], [14]. Since legionnaire’s disease is indistinguishable from other forms of pneumonia without diagnostic testing, the Infectious disease society of America (IDSA) and American thoracic society (ATS) guidelines for CAP recommend to include empirically an antibiotic therapy regimen that covers legionella species, such as fluoroquinolones or macrolides [15]. What makes this case stand out is that in unfortunate patients, a delay in the diagnosis and treatment may lead to extrapulmonary manifestations such as lymphadenitis and will be associated with worse patient outcomes. Despite appropriate management in our institution, the outcome of the disseminated legionellosis infection was catastrophic and did lead to the patients’ death.

Conclusion

Legionella is an important cause of community acquired pneumonia which if left untreated can become complicated with extrapulmonary manifestations such as lymphadenitis and become eventually fatal to patients. A prompt early diagnosis and appropriate antimicrobial therapy covering legionella should be considered whenever treating community acquired pneumonia.

Ethical approval

This case report has been approved by the ethics committee of Mount Lebanon Hospital, Hazmieh, Lebanon.

Funding

No financial support to be disclosed.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the case.

Patients or the public WERE NOT involved in the design, or conduct, or reporting, or dissemination plans of our research. Appropriate consent form was filled by a relative of the patient (sister) and is available upon request.

CRediT authorship contribution statement

Johny Salem: Writing – review & editing, Writing – original draft, Software, Resources, Methodology, Formal analysis, Conceptualization. Fadi Fares: Writing – original draft, Resources, Investigation, Data curation. Rana El-Haddad: Visualization, Validation, Project administration. Mirna Fares: Validation, Project administration, Methodology, Conceptualization. Gilbert El-Helou: Writing – review & editing, Writing – original draft, Validation, Project administration.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.