Diagnosing L. pneumonia first presenting digestive signs



In contrast to commonplace community-acquired pneumonia, Legionella pneumonia has various scientific signs, regularly accompanied through failure within the serve as of multi-system, together with diarrhea and increased liver enzymes within the digestive formulation, acute left middle failure within the circulatory formulation, and higher WBC within the hematological formulation. As a result of the loss of standard scientific manifestations and laboratory signs, the loss of specificity of imaging manifestations, the trouble of tradition of Legionella, the low sensitivity of urinary antigen and the very long time required to extend the antibody titer,1 it’s nonetheless tricky to diagnose Legionella an infection when compared with different bacterial infections. Legionella pneumonia is essentially the most critical type of bizarre pneumonia, with an untreated mortality charge of 45.0%.

Legionella pneumonia can also be sporadic or epidemic disseminated, with hospital-acquired infections being the principle direction.2 The analysis is typically in keeping with a clinical historical past of publicity to infected water assets and multisystemic signs out of doors of the affected person’s breathing formulation. If Legionella an infection is being thought to be clinically, although there’s a unfavorable tradition and antibody check, Legionella antibodies nonetheless wish to be thought to be.

Since Legionella species are intracellularly parasitic, antimicrobial brokers will have to be decided on that may simply input lung tissue, airway secretions and feature top intracellular drug concentrations. Macrolides are recurrently used within the remedy of Legionella pneumonia, and new macrolide antimicrobials similar to azithromycin and clarithromycin are actually extra broadly used than erythromycin. Fluoroquinolones similar to moxifloxacin and gatifloxacin even have just right anti-legionella process.3 Rifampin is regularly used clinically together with macrolide antimicrobials within the remedy of critical Legionella pneumonia. Alternatively, rifampicin resistance and unintended effects prohibit its use.4 In abstract, well timed analysis and competitive remedy can successfully beef up the diagnosis of this bacterial an infection.

Case Document

A 75-year-old feminine, was once transferred to the dept of pulmonary and significant care medication of our health center on July 5, 2019, with a 5 days historical past of nausea, vomiting, and fever. Within the afternoon of June 29, after taking a scorching spring tub in a global lodge in an city field, nausea and vomiting seemed at 6 o’clock tomorrow. The vomit was once abdomen contents and bile, accompanied through fatigue, chills, dizziness, belly discomfort, no cough, sputum, muscle ache, and many others., and no temperature was once measured. Those signs had been alleviated after the affected person took Paracetamol, Caffein, Synthetic Cow-bezoar and chlorphenamine Maleate pills orally. On July 1, the above signs reemerged and worsened, she was once admitted to the overall surgical operation division with a frame temperature of 37.8°C. A computed tomography (CT) scan of her stomach confirmed gallbladder calculi (2.0*1.7cm) and fatty infiltration of pancreatic tissue. She have been recognized with cholecystitis and gallbladder neck stones, those signs progressed moderately after remedy with out a nutrition, metronidazole, cefoperazone sulbactam, and rehydration. On July 2, She had chills and frame temperature rose to 39.2°C, after she was once given dexamethasone and bupleurum (A Chinese language conventional medication) for muscle injection to cut back the fever, the frame temperature returned to customary. The frame temperature rose once more to a most of 39.6°C within the early morning of the 4th, and fluctuated at 38.0–38.6°C after giving dexamethasone and oral paracetamol. In the meantime, the affected person offered with shortness of breath with out cough and sputum. Making an allowance for the opportunity of unusual pathogens, levofloxacin was once added and metronidazole was once stopped at the similar day. The chest CT confirmed interstitial adjustments and lobular exudate shadow in each lungs, with evident manifestation in each decrease lungs (see Determine 1A).

Determine 1 Chest CT ahead of and after remedy (A) on July 4, 2019, early onset, out of health center; (B) on July 12, 2019, when the situation changed into worse after admission; (C) on July 22, 2019, after remedy, the affected person’s situation progressed; (D) on August 12, 2019, re exam was once performed after discharge.

The affected person had a historical past of arterial high blood pressure for 10 years, Kind 2 diabetes for 30 years. Glycemic was once typically in deficient keep an eye on with common use of Aspart 30R insulin (28-14-28 IU) ahead of 3 foods. Cystic adenoma-ectomy of the suitable thyroid gland got rid of 29 years in the past.

The affected person was once transferred to division of pulmonary and significant care medication on July 5, 2019. Exam confirmed that: T37.5°C, Center Price 104 beats/min, BP 128/56 mmHg, Breathing charge 36/min, transparent awareness, Bodily exam cooperation, lips cyanosis, coarse breath sounds in each lungs, rainy rales audible in each decrease lungs, evident in the suitable lung, No abnormality present in different bodily examinations. Auxiliary examinations: regimen blood check (2019-07-04): WBC 17.31×109/l, NEU% 85.1%, LYMPH% 8.6%, PLT 81×109/L. Blood gasoline research (2019-7-02, oxygen 2L/min): PH 7.42, PCO2 29.8mmHg, PO2 67mmHg, SO2 92.7%, Okay+ 3.3mmol/l. Chest CT (2019-7-4, Determine 1A): interstitial adjustments and lobular exudates in each lungs, with bilateral decrease lungs being essentially the most outstanding. Oxygen was once administered through garage masks at 8L/min, oxygen saturation fluctuated at 90–92%, shortness of breath was once obvious, fever was once provide, and frame temperature was once as much as 39.2°C. Blood gasoline research confirmed: sO2 80.1%, PO2(A-a) 179.6mmHg, Okay+ 2.31mmol/L, Na+ 131.6mmol/L, PH 7.343, PCO2 27.4mmHg, PO2 48.7mmHg; pO2(a)/FIO2 118.7mmHg;

The affected person’s blood depend confirmed a vital building up in neutrophils, and more than one sputum cultures confirmed Pseudomonas tropicalis and Pseudomonas albicans, which have been proof against fluconazole, itraconazole, and voriconazole, and delicate to 5F-flucytosine and amphotericin B. The urinary antigen of Legionella pneumophila kind 1 was once monitored as sure through the provincial CDC; Pharyngeal swabs and full blood Legionella nucleic acid exams had been unfavorable. The affected person underwent chest radiography on 07/07/2019 appearing vital development of bilateral lung lesions (Determine 2A), and was once modified to tracheal intubation ventilator-assisted respiring (top PEEP, small tidal quantity) at 21:00 at the similar day because of unsustainable oxygen saturation; the next day to come, the chest radiograph (see Determine 2B) confirmed absorption of bilateral lung lesions in comparison to the former one, and because the situation progressed, the ventilator parameters had been progressively adjusted downward, and the affected person was once effectively discharged from the ventilator on 2019-07-13, and then the frame temperature dropped. After admission, the supply of an infection of the affected person was once thought to be to be legionella. Moxifloxacin and azithromycin got to regard the affected person. The affected person’s situation persevered to become worse. Tegacycline was once added to the affected person. The sputum was once cultured for a number of occasions as Candida tropicalis and Candida albicans. Kapofengin was once given antifungal remedy. On the similar time, 40 mg methylprednisolone was once used on the time of admission. The drug was once stopped 4 days later, and human serum albumin was once injected to proper hypoproteinemia. After lively remedy, the chest CT (see Determine 1B) was once reexamined on July 12. The lesion was once clearly absorbed, and the affected person had no fever. The overall situation was once OK, Second look of chest CT on July 22 (see Determine 1C) The lung lesions are nonetheless being absorbed. After discharge, the affected person was once adopted up on August 12 and left outdated wire strips on chest CT (see Determine 1D).

Determine 2 Chest X-ray exam after admission (A) on July 7, 2019, when the situation worsened; (B) on July 8, 2019, when the situation progressed moderately.


Legionella spp., a gram-negative polymorphic bacillus this is recurrently present in more than a few water environments and wet soils,5 particularly in air conditioners, water provide methods similar to faucet water, cooling towers and showers, which might be carefully associated with day-to-day existence.6,7 The epidemic season of Legionella an infection peaks in summer season and autumn, and the an infection is principally transmitted through inhalation of Legionella with aerosols and aerosols throughout the breathing tract, in addition to unintended inhalation of water containing Legionella spp. The scientific manifestations of delicate Legionella infections are very similar to the ones of influenza infections, whilst some instances display critical injury to more than one organs of the frame, principally within the lungs, liver, spleen, kidneys, digestive tract and central frightened formulation.8 There also are studies of instances during which the primary presentation was once with gastrointestinal signs.9 The analysis of Legionella pneumonia is in keeping with intrapulmonary and extrapulmonary scientific manifestations and CT imaging development of lung infiltrates, sure laboratory cultures of Legionella spp. in sputum, blood or pleural fluid (on particular media); or fluorescent antibodies in breathing secretions; or 4-fold building up or lower in IgG titer through oblique fluorometric exam of blood (or IgG antibody titer ≥1:128).10

The onset of this affected person was once a gaggle tournament with a historical past of publicity to the similar water supply. The affected person’s first symptom was once the digestive formulation. Originally of the onset, the indications of the digestive tract, similar to nausea and vomiting, had been evident, whilst the breathing signs had been delicate, with fever. The chest radiograph confirmed interstitial adjustments in each lungs. The urinary legionella antigen was once sure. Even if the throat swabs and full blood legionella nucleic acid exams had been unfavorable, many research confirmed that urine antigen detection of Legionella is extremely particular (99.1–99.5%).11

Legionella pneumonia has a posh scientific presentation, varies broadly in severity, which is carefully associated with host protection serve as and immune reaction capability. Earlier research have proven that possibility elements for Legionella pneumonia come with smoking, male gender, immunosuppressant use, diabetes, continual lung illness, and renal failure.12,13 On this case, the affected person was once of complicated age, affected by poorly managed blood glucose and blood power. After bacterial invasion of the alveoli, more than one lobes of the lungs had been simply concerned, or even some organ purposes failed, ensuing within the affected person’s essential situation.

Because the affected person’s dyspnea signs worsened, chest X-ray confirmed a vital building up in bilateral infiltrates, oxygen saturation may now not be maintained. After the affected person tracheal intubation and invasive ventilator-assisted respiring and sure PEEP fashion was once carried out, the affected person’s oxygen saturation temporarily higher. Day after today, the chest X-ray confirmed each lungs with bilateral infiltrates had been considerably absorbed, and it was once inferred that the infiltrates had been inflammatory exudates, which have been associated with the higher permeability of alveolar capillaries. Speedy growth of the affected person’s alveolar capillary permeability allowed for efficient restore of the broken alveolar epithelial barrier, decreasing hypoxemia and the affected person’s mortality, and the early use of the ventilator on this case was once the important thing to a hit remedy.

The affected person’s early lung irritation was once delicate, and the aged’s digestive tract serve as was once disordered. To start with, the immune irritation of the digestive tract was once outstanding. With the growth of the illness, the lung irritation changed into worse, and cough and dyspnea befell.

Legionella pneumonia isn’t uncommon and would possibly motive higher morbidity and mortality if unrecognized or improperly remedy. It’s been reported that new macrolide and quinolone antibacterial brokers which might input into cells are really useful for the remedy of Legionnaires’ illness. Early management of suitable antibiotics is paramount for a hit remedy. In a different way, the mortality charge of Legionnaires’ illness has been reported to be 60–70%, and the usage of suitable antibiotics can scale back the mortality charge to ten–20%.14 The affected person was once to begin with thought to be to have cholecystitis and consulted usually surgical operation, and the failure to hide Legionella with metronidazole and cephalosporin antibiotics was once probably the most causes for additional exacerbation of the illness. Azithromycin blended with moxifloxacin was once given and breathing signs persevered to aggravate, with slow growth after the addition of tigecycline. Legionella species are intracellular pathogens, antibiotics with ok intracellular penetration are much more likely to be efficient. Tegacyclin is a brand new form of glycylcyclin antibacterial drug. It might probably block tRNA from getting into the A web page and inhibit the interpretation procedure through reversibly binding to 16S rRNA. The affinity of tegacyclin to ribosomes is 20 occasions upper than that of alternative tetracyclines;15 it’s been discovered that the intracellular focus of tegacyclin is considerably upper than doxycycline, and when studied in guinea pig fashions, it’s been proven to be lively in opposition to Legionella pneumophila throughout lively enlargement.16 In human monocyte derived macrophages, when compared with levofloxacin and erythromycin, tegacyclin has deficient process in opposition to Legionella pneumophila within the extracellular time killing find out about, however within the intracellular time killing experiment, it has more potent process than levofloxacin and erythromycin, whilst the deficient process in vitro could also be associated with the inactivation of tegacyclin within the tradition medium.17 Valve et al18 have effectively used tegacyclin to regard legionella pneumonia in sufferers with low immune serve as. Some students imagine that tegacyclin can be utilized as a second-line drug or a mix drug for critical legionella an infection.16 Additional potential research are essential to verify those findings.

Some research have proven that inhibiting the over the top immune inflammatory response in sufferers with critical pneumonia can beef up the scientific diagnosis and scale back mortality. Glucocorticoid is without doubt one of the best anti inflammatory medication in scientific software, which is able to exert its anti inflammatory impact through affecting various sign transduction pathways; Alternatively, long-term use would possibly scale back the frame’s talent to shield in opposition to irritation, thereby inflicting the deterioration of an infection. It’s been showed through students that if sufferers with critical community-acquired pneumonia are accompanied through critical immune inflammatory response, they are able to be given 0.5 mg/kg of methylprednisolone for five days, which is of serious importance to beef up the luck charge of remedy and scale back the chance of demise, and will scale back the failure charge of remedy.19 On this case, methylprednisolone is given for 4 days, bearing in mind that the affected person has diabetes, and long-term use of corticosteroids is an immunosuppressant, After the affected person’s situation progressed, the drug was once stopped decisively to keep away from connected unintended effects. Subsequently, extra scientific proof is had to verify the worth, timing and dosage of glucocorticoid.


Via this situation we realized that sufferers with Legionella pneumonia can growth hastily in a brief time frame if they aren’t handled promptly, early scientific analysis and remedy are essential. The analysis of extremely suspected sufferers can’t be made most effective through laboratory exams, however well timed management of gear to keep an eye on the illness, scale back headaches and beef up the diagnosis.

Observation of Ethics

This analysis complies with the ideas for human research and is based on the Declaration of Helsinki. This paintings was once authorized through the clinical ethics committee of the First Health facility of Shanxi Scientific College, China (No. [2020]-02-246-01). Consent was once bought from the affected person for participation on this find out about and the e-newsletter of related knowledge together with radiological pictures. The authors showed that private identification data of the affected person knowledge was once unidentifiable from this record.


We thank Hong Kang for offering the technical help.


Supported through the Non-profit Central Analysis Institute Fund of Chinese language Academy of Scientific Science (2020-PT320-005).


The authors claim no conflicts of pastime on this paintings.


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