Tropheryma whipplei infection in the lung of a patient with long COVID: a case report

BACKGROUND

Immune dysregulation in individuals with long COVID has been detected. Differential diagnosis of diffuse infiltration on chest CT in long COVID is challenging.

CASE PRESENTATION

A 62-year-old man presented with a 10-month history of dyspnea after COVID-19 infection. Dyspnea became worse in the one month preceding presentation. The chest CT showed multifocal, subpleural, bilateral opacities due to long-COVID, and infiltration around the bronchovascular bundle in the bilateral lower lung field. The pathology for the transbronchial cryobiopsy (TBCB) first reported chronic inflammation (mainly interstitial pneumonia). The patient had positive results on tests for the antibody, RO-52+, EJ+. The presumptive diagnosis of connective tissue disease-interstitial lung disease was made. Prednisone and cyclophosphamide were given. At follow-up one month later, the chest CT showed new diffuse ground-glass infiltration. The previous TBCB specimen was re-evaluated. Foamy macrophages were found in the alveolar air space. Periodic acid-Schiff (PAS) staining was performed. Numerous intracytoplasmic organisms were detected, with morphologic features consistent with those of Tropheryma whipplei. The patient recovered after intravenous ceftriaxone and oral trimethoprim-sulfamethoxazole. The final diagnosis was lung T. whipplei infection and long COVID-19.

CONCLUSION

This is the first case report of Tropheryma whipplei infection in the lung of a patient with long COVID-19. T. whipplei should be considered as a potential pathogen for diffuse lung infiltration in the post-COVID-19 era.

Intrauterine colonization with Gardnerella vaginalis and Mobiluncus mulieris induces maternal inflammation but not preterm birth in a mouse model

PROBLEM

Preterm birth (PTB) remains a leading cause of childhood mortality. Recent studies demonstrate that the risk of spontaneous PTB (sPTB) is increased in individuals with Lactobacillus-deficient vaginal microbial communities. One proposed mechanism is that vaginal microbes ascend through the cervix, colonize the uterus, and activate inflammatory pathways leading to sPTB. This study assessed whether intrauterine colonization with either Gardnerella vaginalis and Mobiluncus mulieris alone is sufficient to induce maternal-fetal inflammation and induce sPTB.

METHOD OF STUDY

C56/B6J mice, on embryonic day 15, received intrauterine inoculation of saline or 108 colony-forming units of G. vaginalis (n = 30), M. mulieris (n = 17), or Lactobacillus crispatus (n = 16). Dams were either monitored for maternal morbidity and sPTB or sacrificed 6 h post-infusion for analysis of bacterial growth and cytokine/chemokine expression in maternal and fetal tissues.

RESULTS

Six hours following intrauterine inoculation with G. vaginalis, M. mulieris, or L. crispatus, live bacteria were observed in both blood and amniotic fluid, and a potent immune response was identified in the uterus and maternal serum. In contrast, only a limited immune response was identified in the amniotic fluid and the fetus after intrauterine inoculation. High bacterial load (108 CFU/animal) of G. vaginalis was associated with maternal morbidity and mortality but not sPTB. Intrauterine infusion with L. crispatus or M. mulieris at 108 CFU/animal did not induce sPTB, alter pup viability, litter size, or maternal mortality.

CONCLUSIONS

Despite inducing an immune response, intrauterine infusion of live G. vaginalis or M. mulieris is not sufficient to induce sPTB in our mouse model. These results suggest that ascension of common vaginal microbes into the uterine cavity alone is not causative for sPTB.

Subcutaneous Nodules Caused by Tropheryma whipplei Infection

To help clarify the clinical manifestations, diagnosis, and treatment for Whipple disease, we report a case of a man in China infected with Tropheryma whipplei. The patient had multiple subcutaneous nodules as the only manifestation, which was not consistent with the typical symptoms of T. whipplei infection.

Tropheryma whipplei endocarditis in Spain: Case reports of 17 prospective cases

Tropheryma whipplei endocarditis is an uncommon condition with very few series and <90 cases reported in the literature. The aim of the study was to analyze the epidemiological, clinical, and outcome characteristics of 17 cases of T. whipplei endocarditis recruited in our country from a multicentric cohort from 25 Spanish hospitals from the Spanish Collaboration on Endocarditis-Grupo de Apoyo al Manejo de la Endocarditis infecciosa en España.From a total of 3165 cases included in the cohort, 14.2% were diagnosed of blood culture negative endocarditis (BCNE) and 3.5% of these had T. whipplei endocarditis. This condition was more frequent in men. The average age was 60.3 years. Previous cardiac condition was present in 35.3% of the cases. The main clinical manifestation was cardiac failure (76.5%) while fever was only present in the 35.3%. Ecocardiography showed vegetations in 64.7% of patients. Surgery was performed in all but 1 cases and it allowed the diagnosis when molecular assays were performed. A broad range rRNA 16S polymerase chain reaction was used for first instance in all laboratories and different specific targets for T. whipplei were employed for confirmation. A concomitant Whipple disease was diagnosed in 11.9% of patients. All patients received specific antimicrobial treatment for at least 1 year, with no relapse and complete recovery.T. whipplei endocarditis is an uncommon condition with an atypical presentation that must be considered in the diagnosis of BCNE. The prognosis is very good when an appropriate surgical management and antimicrobial-specific treatment is given.

Rhodococcus equi pericarditis in a patient living with HIV/AIDS

INTRODUCTION

Rhodococcus equi, previously called Corynebacterium equi, is known to cause pneumonia in foals and swine. Although it was known to cause infection rarely in humans, R equi infection in humans has increased with the advent of HIV and increased use of immunosuppressants.

CASE

We report a case of a 48-year-old male patient with newly diagnosed HIV/AIDS presenting with recurrent R equi bacteremia, pericardial effusion, and pericardial cyst. The infection was treated with drainage of the pericardial effusion and cyst and 2 weeks of intravenous vancomycin and 6 months of oral azithromycin and levofloxacin.

DISCUSSION

Rhodococcus equi causes pericarditis and pericardial effusion. It can be effectively treated with debridement, drainage, and a prolonged course of antibiotics. In vitro antibiotic susceptibility should be checked as resistance to antibiotics can develop, especially if drainage is inadequate.

Rothia endocarditis in a child

Rothia dentocariosa, an organism inhabiting the oral flora, has been reported to cause endocarditis in adults but not in children. Most patients reported with Rothia endocarditis have a history of poor dentition. We report a case of Rothia endocarditis in a child with congenital heart disease without other known risk factors.

Cloning of genes that have environmental and clinical importance from rhodococci and related bacteria

Generalised and specialised transduction systems were developed for Rhodococcus by means of bacteriophage Q4. The latter was used in conjunction with DNA from an unstable genetic element of R. rhodochrous to construct resistance plasmids which replicate in strains of R. equi, R. erythropolis and R. rhodochrous. One of the plasmids, pDA21, was joined with Erythropolis coli suicide vector pEcoR251 to obtain shuttle plasmids maintained in both rhodococci and E. coli. Conjugation between these rhodococcal strains demonstrated all were interfertile with each other and that some of the determinants for this were located on the unstable genetic element. Plasmids derived from this element, such as pDA21, carried the conjugative and self-incompatibility capacities; deletion analysis revealed that DNA necessary for self-incompatibility overlapped with that for arsenic resistance. Rifampicin is one of the principal chemotherapeutic agents used to treat infections by rhodococci and related organisms. The genes responsible for two types of inactivation have been cloned. The sequence of the R. equi DNA responsible for decomposition of the antibiotic strongly resembled those of monooxygenases acting upon phenolic compounds, consistent with the presence of a naphthalenyl moiety in the rifampicin molecule. Antibiotic resistance conferred by the gene was surprisingly specific to the semisynthetic compounds rifampicin (150-fold increase) and rifapentine (70-fold). Similar specificity was observed with the other inactivation gene cloned, which ribosylates rifampicin at the 23-hydroxyl position. A 60-bp sequence upstream of the monooxygenase and ribosylation genes is strikingly similar suggesting a shared pattern of regulation. Rhodococcal arsenic resistance and azo dye degradation genes have been cloned and characterised.

MICROMORPHOLOGY OF DERMATOPHILUS CONGOLENSIS

Gordon, Morris A. (Division of Laboratories and Research, New York State Department of Health, Albany), and Mercedes R. Edwards. Micromorphology of Dermatophilus congolensis. J. Bacteriol. 86:1101-1115. 1963.-As seen in electron micrographs of thin sections, Dermatophilus congolensis is a holocarpic actinomycete that fragments, after formation of septa in several planes, into Sarcina-like packets and then into individual cocci. Release of coccal forms from the filaments and packets is by dissolution of a capsular matrix, which is a product of degradation of the cell wall. The plasmalemma is a "unit membrane." Regularly occurring plasmalemmosomes ("onion bodies") of uniform structure are apparently related to septum formation. A typical bacterial nucleoid is seen in most sections, and ribosomes are scattered throughout the cytoplasm. Specimens for electron microscopy were prepared by a modification of Kellenberger's method.

Endocarditis caused by Arcanobacterium haemolyticum

A 33-year-old, active intravenous drug-abusing male infected with the human immunodeficiency virus developed endocarditis due to Arcanobacterium haemolyticum. Empirical treatment with ampicillin plus gentamicin failed to achieve a marked clinical improvement. When the results of antibiotic susceptibility were available (ampicillin MIC < or = 0.06 mg/l; ampicillin MBC 2 mg/l; MBC:MIC ratio > 32) therapy was changed to vancomycin plus gentamicin. During the following days progressive clinical and radiological improvement was observed. The patient received antibiotics for 30 days and no relapse occurred during a 14-month follow-up. The literature of endocarditis due to this uncommon bacterium is reviewed here.

[New bacterial infections in the course of AIDS]

The authors reviewed the recent data on unusual or newly described bacterial infection in AIDS. Mycoplasma species are frequently associated with AIDS and hypothesized to play as a cofactor in AIDS evolution (Mycoplasma fermentans and Mycoplasma penetrans). Rochalimea henselea and Rochalimea quintana are the agents of peliosis and bacillary angiomatosis. Some Mycobacterium and Campylobacter species, not previously considered as human pathogens, have been recently involved in severe infection in patients with AIDS.

[An experimental study of the mechanism of shock-induced enterogenic infection after long-term standard total parenteral nutrition]

In this study, gnotobiotic rats were subjected to total parenteral nutrition (TPN) and subsequent hemorrhagic shock to study the mechanism of enterogenic infection in these circumstances. (1) Long-term (8-12 days) TPN induced impairment of gut barrier function, evidenced by atrophy of intestinal mucosa, significant decrease in diamine oxidase activity of intestinal mucosa and blood, and marked micro-ecologic imbalance of the intestinal mucosa flora with dominant growth of aerobes and relative decrease in anaerobes. The degree of mucosal damage were proportional to the duration of TPN. (2) In TPN+shock groups, further damage was found in the mucosa, with a large number of invading gram-negative organisms and a significant decrease in DAO activity as compared to that with TPN only groups. These changes were significantly correlated with enhanced bacterial translocation, elevation of LPS and MDA levels in the plasma. These findings suggested that long term TPN impairing gut barrier function, precipitated posttraumatic gut barrier failure. The determination of plasma DAO activity may help in the early diagnosis of gut injury during TPN and after trauma.

[Pulmonary infection caused by Rhodococcus equi in a renal transplant recipient]

Rhodococcus equi is a primarily pathogen in animals and it has only rarely been seen in immunocompromised humans. We describe our experience with an HIV-negative patient with a functioning renal graft under cyclosporin-azathioprine-prednisone therapy. The patient died after a two months recurrent multifocal pneumonia. The cultures from sputum and blood were negatives but R. equi was isolated from lungs in the necropsy. Most of the 41 cases we had found in the literature had AIDS or HIV infection. Six cases had a kidney graft under azathioprine-prednisone therapy. Rhodococcus equi infection may be missed in some instances due to incomplete or improper identification of the organism, that grows well in aerobic media but is usually regarded as a component of normal flora or as a contaminant. The ability of R. equi to persist in and eventually to destroy macrophages is the basis of its pathogenicity. It also explains the clinical resistance to antibiotics without intracellular activity. Rhodococcus equi infection must be suspected in immunocompromised patients with recurrent pneumonia. Correct identification and combined therapy with lipophilic antibiotics that penetrate the macrophages are necessary to prevent the high mortality of this infection.

Actinomycete infections in humans--a review

Diseases caused by pathogenic aerobic and facultatively anaerobic actinomycetes differ considerably with respect to their etiology, pathogenesis, clinical appearance and epidemiology. Facultatively anaerobic (fermentative) actinomycetes may not only be involved etiologically in the three classical forms of cervicofacial, thoracic and abdominal actinomycoses, but also in infections of the female genital organs, the eye, the tissue adjacent to dental implantation elements and tooth extraction wounds. The species distribution of the fermentative actinomycetes isolated from these conditions varied to a certain, but characteristic, extent, as did the concomitant actinomycotic flora. The sex ratio reported for human Actinomyces infections (male:female = 3:1) appeared to be restricted to actinomycotic abscesses and empyemas. The prevailing pathogenic, obligately aerobic actinomycete species in Germany was found to be Nocardia farcinica followed by Nocardia asteroides. The comparatively high incidence of N. farcinica infections was chiefly due to the occurrence of nosocomial postoperative wound infections by this pathogen observed in two German hospitals. Besides surgical treatment, immunosuppressive treatment appeared to be the most common factor predisposing for nocardiosis. Recent observations strongly suggested that the spectrum of human nocardial infections in Germany has been changing, as regards the overall incidence, the prevalence of N. farcinica, the sex ratio, the mean age of patients, as well as the role of N. farcinica as a possibly important nosocomial pathogen.

Lung abscess caused by Rhodococcus equi

In the immunocompromised patient, early diagnosis of a lung cavity is essential for appropriate treatment. Rhodococcus equi (formerly Corynebacterium equi) is a variably acid-fast bacterium that can produce cavitary disease in an immunocompromised host. The two cases presented here demonstrate the clinical and radiographic features of R equi lung abscess. The first patient was on long-term corticosteroid therapy for rheumatoid arthritis. The second patient had AIDS. The correct diagnosis in both cases was delayed because acid-fast bacilli seen on smears of sputum were presumed to be Mycobacterium tuberculosis.

Rhodococcus peritonitis in a patient treated with peritoneal dialysis

This report is of a patient treated with continuous ambulatory peritoneal dialysis who developed peritonitis attributed to a Rhodococcus species. The rhodococci are rarely pathogenic to humans, and there are no previous reports of peritonitis associated with these organisms. It is important for clinicians to be aware of these bacteria because they can be acid-fast and can be confused with mycobacteria. They are often reported as "diphtheroids" but should not be considered contaminants.

Osteomyelitis caused by Rhodococcus equi in a renal transplant recipient

We report the first case of osteomyelitis due to Rhodococcus equi, which occurred in a renal transplant patient. Infection with this organism is rare and usually causes a distinct clinical syndrome resembling pulmonary tuberculosis. We investigated by time-kill curve analysis various antimicrobial combinations for in vitro efficacy. The literature is briefly reviewed, and aspects of diagnosis and therapy are discussed.

Actinomycetoma caused by Rhodococcus spp

We report a case of mycetoma caused by Rhodococcus in a 62-year-old man who presented with multiple draining sinuses of the left foot. Biopsy specimen showed granulomatous reaction and microabcesses contained granules. These granules were composed by rod and coccoid Gram-positive and partially acid-fast elements. Culture grew a 'Nocardia-like organism', confirmed at the Center for Disease Control as Rhodococcus spp.

Mycetoma of the head and neck

Cranial mycetoma is not as rare as was believed. In the Sudan, the majority of cases are caused by S. somaliensis; no cases were found to be caused by Nocardia species. Cranial actinomycetoma proved to be potentially fatal and was the most difficult to treat. The best treatment results were achieved in cases of A. madurae infection.

Actinomycetoma caused by Nocardiopsis dassonvillei

We report a case of mycetoma caused by Nocardiopsis dassonvillei in a 39-year-old man. He had multiple nodules and draining sinuses on the anterior aspect of his right leg just below the knee. Few cream-colored granules were seen in the exudate. The biopsy specimen showed gram-positive, non-acid-fast granules with distinct borders. An aerobic actinomycete isolated from the lesion was identified as N dassonvillei. We think that this is the first reported case of mycetoma caused by N dassonvillei.

The aetiological agent of cat scratch disease

A highly pleomorphic, gram-positive bacterium was cultured from an excised lymph node of a patient with cat scratch disease (CSD). The organism had morphological forms similar to those of the bacterium observed in Warthin-Starry stains of lymph node sections from CSD patients and may be the aetiological agent of this disease. Electron microscopic examination of lymph node sections from another patient with CSD showed organisms with morphological forms similar to those of the isolated bacterium. Biochemical and physiological analyses of this isolate suggested that it is not a commonly recognised contaminant or human pathogen and that it may be a member of the genus Rothia. This organism appears to resemble the bacterium that was identified as the aetiological agent of Parinaud's oculoglandular syndrome, a specific form of CSD, over 70 years ago.

Endocarditis caused by Rothia dentocariosa

A case of infective endocarditis caused by Rothia dentocariosa is described in a 53 year old man with a history of rheumatic fever. R dentocariosa is a component of the oral microbiota and has only rarely and recently been recognised as a human pathogen. In this patient the oral flora was the probable source of infection, with a broken molar tooth providing the probable avenue for infection.

Structural studies on an antitumor polysaccharide from Microellobosporia grisea

The structure of the antitumor polysaccharide from the actinomycete Microellobosporia grisea has been investigated. By methylation and periodate-oxidation studies, the polysaccharide was shown to consist of (nonreducing) D-mannosyl groups, (1 leads to 4)-linked D-glucosyl residues, and 3,6-branched, (1 leads to 4)-linked D-glucosyl residues in the approximate molar ratios of 2:1:1. Periodate oxidation of the polysaccharide, followed by borohydride reduction and mild hydrolysis with acid yielded glycerol, erythritol, 2-O-beta-D-glucopyranosyl-D-erythritol, and 5-O-beta-D-glucopyranosyl-2,4-bis(hydroxymethyl)-1,3-dioxane, which were isolated in the molar ratios of 2.0:0.14:0.74:0.35. Partial hydrolysis of the polysaccharide gave alpha-D-Manp-(1 leads to 6)-D-Glcp, beta-D-Glcp-(1 leads to 4)-D-Glcp, alpha-D-Manp-(1 leads to 3)-D-Glcp, and beta-D-Glcp-(1 leads to 4)-[alpha-D-Manp-(1 leads to 3)-]-D-Glcp. From these results, it is proposed that the polysaccharide is mainly composed of tetrasaccharide repeating-units having the following structure. (formula: see text)

Bacterionema matruchotii ocular infections

One case of endophthalmitis and two cases of corneal ulceration, each occurring in a structurally altered eye, were associated with Bacterionema matruchotii, a gram-positive filamentous bacillus.

Exogenous mycotic infections of the eye and adnexia

Three cases of exogenous mycotic infections of the eye are presented. The first is a case of keratitis in a patient suffering from glaucoma simplex who removed a foreign body from the cornea, caused by Fusarium solani, generally known as a saprophytic soil and plant inhabitant. As factors predisposing the patient to infection, trauma to the cornea like injury by a foreign body, as well as the preexisting disease of the eye, are discussed. The other case illustrates the change in the pathogenicity of an otherwise innocent fungus like Penicillium, which penetrated the sclera after injury of the eye by a broken airpiece of a drill and caused a severe endophathalmitis. The infection responded well to treatment with 5-fluorocytosine. The last case represents a rather mild well-known mycotic infection by Streptomyces somaliensis causing canaliculitis in a patient admitted for cataract surgery. Curettage of the infected canaliculus followed by iodine washout proved to be effective. The importance of the early clinical and laboratory diagnosis in order to avoid mistreatment with antibiotics and steroids and to ensure the right antimycotic treatment is stressed.

A microbial etiology of acne?

The view is advanced that sebum as originally produced must contain materials, other than lipids, which may serve as a selective substrate for growth of bacteria and yeasts. Growth of large numbers of P. acnes and P. granulosum in some follicles is considered to place those follicles at risk of undergoing pathological changes. Deleterious products of bacterial growth could be not only lipase and free fatty acids, but also other enzymes as well as bacterial antigens and unspecified toxins or irritants. The possibility is suggested that follicles heavily infested with P. acnes and P. granulosum may be identified by their reddish fluorescence under ultraviolet light, thus permitting identification and study of those which are at risk. Antibiotics may be helpful in reducing the formation of harmful bacterial products during continued growth of the organisms. The eventually self-limiting nature of the disease may be due to the immune response to bacterial products, or to an accommodation of the follicular epithelium to the long-continued presence of irritant materials within the follicle.

The microbiology of musculoskeletal infection

Of paramount importance in the isolation and identification of bacteria, including mycobacteria, and fungi that cause musculoskeletal infections, are proper selection, collection, and transport of specimens. Material obtained by biopsy, curettage, or aspiration is preferable to that obtained on a swab because too little or unrepresentative material is usually collected on a swab and because swabs cannot be transported readily under conditions favorable to survival of anaerobes. Although actual infections are frequently due to staphylococci, strepococci, Enterobacteriaceae, and Pseudomonadacease, the etiologic agents of chronic lesions may include actinomycetes, brucellae, mycobacteria, and fungi. In chronic lesions, histopathologic examination of biopsy material is an important ancillary procedure. In acute infections, the incidence of gram-negative bacilli, particularly of Enterobacteriaceae and pseudomonads, has increased significantly in recent years.