Tropheryma whipplei and Whipple's disease

Two cases demonstrate an association between Tropheryma whipplei and pulmonary marginal zone lymphoma

BACKGROUND

Marginal zone lymphomas of mucosa-associated lymphatic tissues (MZL of MALT) are a group of indolent B-cell neoplasms, which are thought to arise from chronic antigenic stimulation of B-cells either due to underlying chronic infection or autoimmune disease. Little is known about potential causative pathogens in pulmonary MZL (PMZL), although some data suggests a potential role of Achromobacter (A.) xylosoxidans.

METHODS

An index case of chronic pulmonary colonisation with Tropheryma (T.) whipplei and subsequent development of PMZL was identified by T. whipplei specific PCR and metagenomic next genome sequencing (mNGS). This case prompted a retrospectively conducted analysis of T. whipplei-specific PCRs in lung tissue from PMZL patients (n = 22), other pulmonary lymphomas, and normal controls. Positive results were confirmed by mNGS. A systematic search for T. whipplei and A. xylosoxidans in our in-house mNGS dataset comprising autopsy lungs, lung biopsies and lung resection specimens (n = 181) was subsequently performed.

RESULTS

A 69-year-old patient presented with weight loss and persistent pulmonary consolidation. Subsequent mNGS analysis detected T. whipplei in the resected lung specimen. An antibiotic regimen eventually eliminated the bacterium. However, the consolidation persisted, and the diagnosis of PMZL was made in a second lung resection specimen. A second case of T. whipplei-associated PMZL was subsequently detected in the retrospectively analysed PMZL cohort. Both cases showed comparatively few mutations and no mutations in genes encoding for NF-κB pathway components, suggesting that T. whipplei infection may substitute for mutations in these PMZL. None of the samples in our in-house dataset tested positive for T. whipplei. In contrast, A. xylosoxidans was frequently found in both autopsy lungs and lung biopsy / resection specimens that were not affected by PMZL (> 50%).

CONCLUSIONS

Our data suggests that T. whipplei colonisation of lungs may trigger PMZL as a potential driver. Systematic analyses with larger cohorts should be conducted to further support this hypothesis. The frequent detection of A. xylosoxidans in lung tissue suggests that it is a common component of the pulmonary microbiome and therefore less likely to trigger lymphomas.

Is PAS Stain Necessary to Exclude Whipple Disease in Duodenal Biopsies?

Objective. Whipple disease, caused by Tropheryma whipplei, is a rare infectious condition primarily presenting with malabsorptive diarrhea. Small bowel biopsies typically reveal foamy macrophages containing periodic acid-Schiff-positive/diastase (PAS/D) resistant T. whipplei bacilli, and PAS(D) staining is occasionally requested by clinicians in duodenal biopsies, which are often histologically unremarkable. The yield of PAS(D) staining in such biopsies has never been reported to our knowledge. Methods. The anatomic pathology database was searched for all specimens of duodenal biopsies stained with PAS(D) from 1993 to 2021. Specimens were categorized by the following histomorphologic features: unremarkable, nonspecific changes, or expansion of the lamina propria by aggregates of foamy histiocytes. Follow-up information was collected, including microbiologic confirmatory testing. Results. There was a total of 193 specimens of duodenal biopsies stained with PAS(D). Biopsies lacking foamy histiocytes on H&E (n = 158) were never PAS-positive. Thirteen biopsies contained PAS-positive histiocytes; 9 out of the 13 PAS-positive specimens were subsequently confirmed to be T. whipplei. Of the 193 specimens, 124 specimens had a clinical request for PAS(D) staining. Only 3 of the 124 (2.4%) specimens showed foamy histiocytes containing PAS-positive granules, all of which were confirmed positive for T. whipplei. Conclusion. PAS(D) staining is unnecessary to exclude Whipple disease in duodenal biopsies without foamy macrophage aggregates, regardless of clinical suspicion. Clinical suspicion-driven biopsies often yield negative results for Whipple disease.

Whipple Disease Presenting as Isolated Transverse Myelitis with Permanent Neurological Damage in a Patient with Systemic Lupus Erythematosus: A Case Report of a Difficult Diagnosis with a Literature Review

We describe an atypical case of Whipple disease exclusively involving the spinal cord in an adolescent receiving immunosuppressive therapy for systemic lupus erythematosus. The diagnosis was particularly difficult since lupus and Whipple disease can present similar clinical features and the patient's prolonged contact with sewage was initially not mentioned. A literature review of the clinical, imaging, diagnostic, and therapeutic challenges of Whipple disease is also performed.

Antidiarrheal and antioxidant activities of Ajuga iva (L.) leave extract

We studied the effect of Ajuga iva leaves extract (AIE) on the intestinal absorption, motricity and its antioxidant capacity against diarrhea. Wistar rats were divided and received either: castor oil (CO), CO and loperamide or CO and different doses of AIE. AIE prevented dose-dependently CO-induced diarrhea. AIE at 800 mg/kg showed inhibition efficiency on defecation and diarrhea. The pro-oxidant effect of the CO in the small intestine was inhibited significantly in presence of AIE: increasing glutathione peroxidase (GPx) activity and lowering oxygen free radicals (OH°, O2°-), carbonyl protein and malondialdehyde (MDA) levels. However, co-administration of AIE in castor oil-exposed groups significantly increased the intestinal contents of calcium and magnesium. AIE exhibits significant anti-diarrheal activity, related in part to its antioxidant properties. Our investigation also provides experimental evidence for the traditional use of this medicinal plant in the treatment of diarrhea.

Use of bevacizumab in a patient with Whipple's disease: managing diagnostic uncertainty

A man in his 30s with intellectual disability presented with 1 month of diarrhoea, weight loss and dyspnoea. Investigations were hampered due to significant anxiety. Laboratory tests detected microcytic anaemia and hypoalbuminaemia. CT demonstrated a fat-containing infiltrate in the mediastinum, mesentery and axillae, and pulmonary ground-glass infiltrates. Biopsy of the axilla showed cystic lymphatic malformations involving adipose tissue and lymph nodes, leading to a provisional diagnosis of generalised lymphatic anomaly. Over the subsequent 4 months, the patient's respiratory status deteriorated, leading to type 1 respiratory failure necessitating intubation. After multidisciplinary discussion, a decision was made to trial bevacizumab, an anti-VEGF agent, with subsequent improvement in respiratory status. While intubated, gastroscopy was performed; duodenal biopsies revealed pathognomonic changes of Whipple's disease, confirmed on PCR of duodenal and axillae biopsies. This was deemed the most likely unifying diagnosis; antibiotic treatment was commenced, bevacizumab was ceased, and the patient has remained well after 18 months.

Current knowledge of the immune reconstitution inflammatory syndrome in Whipple disease: a review

Immune reconstitution inflammatory syndrome (IRIS) is characterized by exaggerated and dysregulated inflammatory responses that occur as a result of reconstitution of adaptive or innate immunity. A wide range of microorganisms have been found to be associated with IRIS, such as human immunodeficiency virus (HIV), Mycobacterium and actinobacteria. Whipple disease (WD) is an infectious disorder caused by the Gram-positive bacterium Tropheryma whipplei (T. whipplei) and IRIS also serves as a complication during its treament. Although many of these pathological mechanisms are shared with related inflammatory disorders, IRIS in WD exhibits distinct features and is poorly described in the medical literature. Novel investigations of the intestinal mucosal immune system have provided new insights into the pathogenesis of IRIS, elucidating the interplay between systemic and local immune responses. These insights may be used to identify monitoring tools for disease prevention and to develop treatment strategies. Therefore, this review synthesizes these new concepts in WD IRIS to approach the feasibility of manipulating host immunity and immune reconstitution of inflammatory syndromes from a newer, more comprehensive perspective and study hypothetical options for the management of WD IRIS.

An unusual presentation of a rare disease: acute upper limb ischemia as the presenting symptom of Whipple's Endocarditis, a case report

BACKGROUND

Whipple's disease is known to cause multiple varied systemic symptoms, and is a well-documented cause of culture-negative endocarditis. Endocarditis secondary to Whipple disease, however, has rarely been known to present primarily as a cause of acute limb ischemia. We describe such a case here.

CASE PRESENTATION

A previously healthy 40 year old man presented to the emergency department with acute-onset right arm paresthesias. On exam, he was found to be tachycardic with a VI/VI systolic ejection murmur. He was diagnosed with critical limb ischemia and severe aortic regurgitation, and echocardiography showed a large mass on his bicuspid aortic valve. Thrombectomy was performed urgently, with aortic valve repair the following day. As blood cultures and valvular tissue culture remained unrevealing, the patient remained on empiric vancomycin and ceftriaxone for culture-negative endocarditis. 16 s rRNA nucleic acid amplification testing (NAAT) of his formalin-fixed, paraffin-embedded valvular tissue detected T. whipplei, after which the patient was transitioned to ceftriaxone and trimethoprim-sulfamethoxazole for a year of therapy. He continues to do clinically well.

CONCLUSIONS

We report an unusual presentation of Whipple endocarditis as an acute upper limb ischemia, absent other classic symptoms of Whipple's disease, and with diagnosis made by 16 s rRNA NAAT of valvular tissue in the setting of culture-negative endocarditis.

Design of a Multi-Epitope Vaccine against Tropheryma whipplei Using Immunoinformatics and Molecular Dynamics Simulation Techniques

Whipple’s disease is caused by T. whipplei, a Gram-positive pathogenic bacterium. It is considered a persistent infection affecting various organs, more likely to infect males. There is currently no licensed vaccination available for Whipple’s disease; thus, the development of a chimeric peptide-based vaccine against T. whipplei has the potential to be tremendously beneficial in preventing Whipple’s disease in the future. The present study aimed to apply modern computational approaches to generate a multi-epitope-based vaccine that expresses antigenic determinants prioritized from the core proteome of two T. whipplei whole proteomes. Using an integrated computational approach, four immunodominant epitopes were found from two extracellular proteins. Combined, these epitopes covered 89.03% of the global population. The shortlisted epitopes exhibited a strong binding affinity for the B- and T-cell reference set of alleles, high antigenicity score, nonallergenic nature, high solubility, nontoxicity, and excellent binders of DRB1*0101. Through the use of appropriate linkers and adjuvation with a suitable adjuvant molecule, the epitopes were designed into a chimeric vaccine. An adjuvant was linked to the connected epitopes to boost immunogenicity and efficiently engage both innate and adaptive immunity. The physiochemical properties of the vaccine were observed favorable, leading toward the 3D modeling of the construct. Furthermore, the vaccine’s binding confirmation to the TLR-4 critical innate immune receptor was also determined using molecular docking and molecular dynamics (MD) simulations, which shows that the vaccine has a strong binding affinity for TLR4 (−29.4452 kcal/mol in MM-GBSA and −42.3229 kcal/mol in MM-PBSA). Overall, the vaccine described here has a promising potential for eliciting protective and targeted immunogenicity, subject to further experimental testing.

Challenging case of Whipple's disease: The contribution of radiology

Whipple's disease is a rare chronic infectious disease, caused by Tropheryma whipplei. The disease can be challenging to diagnose due to the variable clinical manifestations and the nonspecific laboratory and imaging findings. We report the case of a 75-year-old man, complaining of weight loss and arthralgias with an insidious onset. A thoracic, abdominal and pelvic CT was performed, demonstrating features suggestive of Whipple's disease. Although not specific, the imaging findings of fatty attenuation mesenteric and retroperitoneal enlarged lymph nodes are a common finding in Whipple's disease. Esophagogastroduodenoscopy with duodenal biopsy confirmed the diagnosis through PCR analysis.

Tropheryma whipplei in the stool samples of children with acute diarrhea: a study from Tehran, Iran

Background

Recently, Tropheryma whipplei has been suggested as one of the causative agents of diarrhea among children worldwide. Limited data is available on the prevalence of T. whipplei among children with diarrhea in most countries such as Iran. This study was conducted to evaluate the prevalence of T. whipplei in children with acute diarrhea in Iran.

Methods

In this study, the stool samples were collected from 130 children under 10 years old with acute diarrhea from children's hospitals in Tehran city. Genomic DNA was extracted from stool samples and was tested for the presence of DNA of T. whipplei using the SYBR Green Real-time PCR method. Positive T. whipplei samples were finally confirmed by PCR Product sequencing.

Results

The mean age of participants was 32.5 months, and 54.6% of children were female. Using the SYBR Green Real-time PCR, 9.23% (12/130) of samples were positive for T. whipplei, which were confirmed by sequencing. 66.67% of positive cases were males. The duration of diarrhea in infected children with T. whipplei (83.3%) was significantly longer (OR: 5.93, 95% CI 1.24–28.22) compared to children with negative results (45.8%). Other demographic factors and clinical signs had not a statistically significant relationship with T. whipplei infection.

Conclusions

In this study, T. whipplei was detected in stool samples of children with acute diarrhea. The results indicated that T. whipplei could be associated with childhood diarrhea in Iran. The health care system and physicians should be aware of the presence of T. whipplei infection in Iran, especially in childhood diarrhea.

Recurrent thrombosis as a clinical presentation of Whipple disease

Whipple's disease (WD) is a rare infectious disease with a wide clinical spectrum. Associated thrombotic manifestations are not well described in WD, only related to 'stroke-like syndrome'. We present a case of a 39-year-old man with a 1-year history of self-limited episodes of fever, associated with generalised adenopathies and recurrent superficial and deep venous thrombosis events, which have resorted four times despite the anticoagulant treatment. Finally, the patient is diagnosed with WD. Following treatment the patient improved in his general condition, and no more episodes of fever neither thrombosis appeared during a follow-up of more than 3 years.

Human galectin-1 and galectin-3 promote Tropheryma whipplei infection

Tropheryma whipplei, is an actinobacterium that causes different infections in humans, including Whipple's disease. The bacterium infects and replicates in macrophages, leading to a Th2-biased immune response. Previous studies have shown that T. whipplei harbors complex surface glycoproteins with evidence of sialylation. However, the exact contribution of these glycoproteins for infection and survival remains obscure. To address this, we characterized the bacterial glycoprofile and evaluated the involvement of human β-galactoside-binding lectins, Galectin-1 (Gal-1) and Galectin-3 (Gal-3) which are highly expressed by macrophages as receptors for bacterial glycans. Tropheryma whipplei glycoproteins harbor different sugars including glucose, mannose, fucose, β-galactose and sialic acid. Mass spectrometry identification revealed that these glycoproteins were membrane- and virulence-associated glycoproteins. Most of these glycoproteins are highly sialylated and N-glycosylated while some of them are rich in poly-N-acetyllactosamine (Poly-LAcNAc) and bind Gal-1 and Gal-3. In vitro, T. whipplei modulates the expression and cellular distribution of Gal-1 and Gal-3. Although both galectins promote T. whipplei infection by enhancing bacterial cell entry, only Gal-3 is required for optimal bacterial uptake. Finally, we found that serum levels of Gal-1 and Gal-3 were altered in patients with T. whipplei infections as compared to healthy individuals, suggesting that galectins are also involved in vivo. Among T. whipplei membrane-associated proteins, poly-LacNAc rich-glycoproteins promote infection through interaction with galectins. T. whipplei modulates the expression of Gal-1 and Gal-3 both in vitro and in vivo. Drugs interfering with galectin-glycan interactions may provide new avenues for the treatment and diagnosis of T. whipplei infections.

Tropheryma whipplei Detection by Nanopore Sequencing in Patients With Interstitial Lung Disease

Tropheryma whipplei is a bacterium associated with Whipple's disease, which commonly manifests as weight loss, arthralgia, and diarrhea. The most frequently involved organs comprise the heart and eyes, in addition to the central nervous system. Few studies have explored the relationship between T. whipplei and pneumonia. Herein, we report three patients with interstitial lung disease (ILD) of unknown cause, whose bronchoalveolar lavage fluid (BALF) were evaluated via Nanopore sequencing. In our in-house BALF Nanopore platform, human DNA was removed with saponin, to improve the reads ratio of microorganisms/host. T. whipplei was the sole or most abundant pathogen in all the patients, comprising 1,385, 826, and 285 reads. The positive result was confirmed via quantitative polymerase chain reaction (PCR) with two pairs of primers (cycle threshold value: 33.26/36.29; 31.68/32.01; 28.82/28.80) and Sanger sequencing. To our knowledge, this is the first report of T. whipplei detection using Nanopore-based sequencing. The turnaround time was approximately 6-8 h in clinical laboratories, including less than 1 h for analysis. In conclusion, the results of this study confirm that Nanopore sequencing can rapidly detect rare pathogens, to improve clinical diagnosis. In addition, diagnosis of Whipple's disease should be combined other laboratory findings, such as periodic acid-Schiff (PAS) staining, and considered a possibility in middle-aged men presenting with ILD and a clinical history of unexplained arthralgia and/or fever.

Treatable Hyperkinetic Movement Disorders Not to Be Missed

Hyperkinetic movement disorders are characterized by the presence of abnormal involuntary movements, comprising most notably dystonia, chorea, myoclonus, and tremor. Possible causes are numerous, including autoimmune disorders, infections of the central nervous system, metabolic disturbances, genetic diseases, drug-related causes and functional disorders, making the diagnostic process difficult for clinicians. Some diagnoses may be delayed without serious consequences, but diagnosis delays may prove detrimental in treatable disorders, ranging from functional disabilities, as in dopa-responsive dystonia, to death, as in Whipple's disease. In this review, we focus on treatable disorders that may present with prominent hyperkinetic movement disorders.

Randomized Trial of Ciprofloxacin Doxycycline and Hydroxychloroquine Versus Budesonide in Active Crohn's Disease

BACKGROUND

Increased mucosa-associated E. coli are present in Crohn's disease, but their role in pathogenesis is uncertain.

AIMS

To assess efficacy and safety of an antibiotic/hydroxychloroquine combination effective against E. coli inside macrophages.

METHODS

Adults with moderately active disease (CDAI > 220-450 plus C reactive protein ≥ 5 mg/l and/or fecal calprotectin > 250 μg/g) were randomized to receive (open-label) oral budesonide (Entocort CR 9 mg/day 8 weeks, 6 mg/day 2 weeks, 3 mg/day 2 weeks) or oral ciprofloxacin 500 mg bd, doxycycline 100 mg bd, hydroxychloroquine 200 mg tds for 4 weeks, followed by doxycycline 100 mg bd and hydroxychloroquine 200 mg tds for 20 weeks. Primary endpoints were remission (CDAI ≤ 150) at 10 weeks, remission maintained to 24 weeks, and remission maintained to 52 weeks. Patients not responding (CDAI fall by > 70) by 10 weeks were invited to crossover onto the alternative therapy.

RESULTS

Fifty-nine patients were recruited across 8 sites. Including crossover, 39 patients received antibiotics/hydroxychloroquine and 39 received budesonide. At 10 weeks, 24 weeks, and 52 weeks on initial therapy, only 2/27, 2/27, and 1/27 were in remission on antibiotics/hydroxychloroquine compared with 8/32, 1/32, and 1/32 on budesonide (P = 0.092 at 10 weeks). Withdrawals by 10 weeks due to adverse events were seen in 15 receiving antibiotics/hydroxychloroquine and 6 budesonide. Results including crossover were more promising with 9/24 patients receiving antibiotics/hydroxychloroquine per protocol in remission by 24 weeks. No correlation was seen between response to antibiotics/hydroxychloroquine and ASCA/OmpC antibody status or disease location.

CONCLUSION

Overall results with this antibiotic/hydroxychloroquine combination were unimpressive, but long-term remission is seen in some patients and justifies further study.

Phenotypic diversity of Tropheryma whipplei clinical isolates

Tropheryma whipplei is a bacterial pathogen responsible for a wide range of infections in humans, covering asymptomatic carriage, acute infections, chronic isolated infections and classic Whipple's disease. Although the bacterium is commonly found in the environment, it very rarely causes disease. Genetic comparison of clinical isolates has revealed that main variations were found in region encoding T. whipplei surface glycoproteins called WiSP. However, no association has been made between the genetic diversity and the clinical manifestations of the infection. In this study we evaluated the phenotypic diversity of 26 clinical isolates from different origins and taken from patient with different infection outcomes. MRC5 and macrophages cells were infected, and bacterial uptake, survival and the pro-and anti-inflammatory potential of the different clinical isolates was assessed. No significant difference of phagocytosis was found between the different isolates; however, we found that bacterial replication was increased for bacteria expressing high molecular weight WiSP. In addition, we found that the expression of the genes coding for IL-1β and TGF-β was significantly higher when MRC5 cells were stimulated with isolates from chronic infections compared to isolates from localized infections while no significant differences were observed in macrophages. Overall, our study revealed that, as previously observed at the genetic level, phenotypic diversity of T. whipplei isolates is associated with the expression of different WiSP, which may result in subtle differences in host responses. Other host factors or genetic predisposition may explain the range of clinical manifestations of T. whipplei infections.

Assessment of the burden of malaria and bacteraemia by retrospective molecular diagnosis in febrile illnesses and first-line anti-infectives in Côte d'Ivoire

BACKGROUND

The aetiologies of fever are poorly understood in sub-Saharan Africa. We aimed to assess the burden of malaria and bacteria in Côte d'Ivoire.

METHODS

Blood samples from 438 febrile and 346 afebrile people were screened using molecular tools.

RESULTS

Plasmodium falciparum was the most common microorganism associated with fever (46.8% in febrile, 23.4% in afebrile people; p < 0.001). Bacteraemia was detected in 21.7% of febrile people and 12.7% of afebrile people (p = 0.001). Streptococcus pneumoniae was the main cause of bacteraemia (7.1% of febrile and 0.6% of afebrile individuals; p < 0.001). Non-typhoidal Salmonella spp. was detected in 4.5% of febrile people and 1.2% of afebrile individuals (p < 0.001). Salmonella enterica Typhi and S. enterica Paratyphi were only detected in febrile subjects (1.4% and 2.1%), as well as Tropheryma whipplei (0.9%), Streptococcus pyogenes (0.7%), and Plasmodium ovale (4.6%). The prevalence in febrile and afebrile people was similar for Staphylococcus aureus (3.6-4.9%), Rickettsia felis (5.5-6.4%), Mansonella perstans (3.0-3.2%), and Plasmodium malariae (1.6-2.3%). Comorbidities were higher in febrile than in afebrile subjects (10.3% versus 5.5%; p = 0.01); 82% involving P. falciparum. All patients co-infected with P. falciparum and S. pneumoniae were febrile whereas 30% of those infected by P. falciparum alone were not (p = 0.02). Among febrile participants, 30.4% with malaria and 54.7% with bacteraemia had received neither antimalarial nor antibiotic therapy.

CONCLUSION

Identification of etiologies of acute febrile diseases in sub-Saharan Africa proposes keys to successful treatment and prevention of infectious diseases. Vaccination campaigns may decrease the morbidity of mono- and co-infections by preventable microorganisms.

Drug Response Diversity: A Hidden Bacterium?

Interindividual heterogeneity in response to treatment is a real public health problem. It is a factor that can be responsible not only for ineffectiveness or fatal toxicity but also for hospitalization due to iatrogenic effects, thus increasing the cost of patient care. Several research teams have been interested in what may be at the origin of these phenomena, particularly at the genetic level and the basal activity of organs dedicated to the inactivation and elimination of drug molecules. Today, a new branch is being set up, explaining the enigmatic part that could not be explained before. Pharmacomicrobiomics attempts to investigate the interactions between bacteria, especially those in the gut, and drug response. In this review, we provide a state of the art on what this field has brought as new information and discuss the challenges that lie ahead to see the real application in clinical practice.

A Case of Whipple Disease With Cutaneous Manifestations

ABSTRACT

Whipple disease (WD) is a rare bacterial infectious disease that is classically characterized by years of arthralgia, followed by malabsorption, diarrhea, and weight loss. However, WD may manifest in virtually any organ system, and patients with WD rarely develop subcutaneous erythema nodosum-like lesions. We report a case of a 51-year-old man diagnosed with WD who subsequently developed widely distributed erythematous subcutaneous nodules after 5 months of antibiotic therapy.

Tropheryma whipplei endocarditis: An uncommon infection with potentially fatal consequences

We report a case of culture-negative aortic valve endocarditis secondary to Tropheryma whipplei infection. Our patient underwent aortic valve replacement after 4 weeks of antibiotic therapy with persistently negative blood culture results. Despite a technically uneventful operation, the patient showed continued sepsis and was unresponsive to a broad-spectrum of antibiotic therapy with subsequent multiorgan failure. He died on the 5th postoperative day, and diagnosis was established at postmortem examination. In this case report, we discuss the diagnosis and treatment of a rare type of endocarditis caused by T. whipplei.

Whipple's Disease: A Rare Cause of Malabsorption Syndrome

Introduction

Whipple's disease is a rare, chronic, systemic disease caused by the actinomycete Tropheryma whipplei. Clinical manifestations vary widely depending on the affected system, the most common being the digestive tract.

Case Presentation

The authors report the case of a 52-year-old man with malabsorption syndrome, diarrhea, marked weight loss, melanoderma, and visual and proprioception disorders. Periodic acid-Schiff staining of a proximal small bowel biopsy and peripheral-blood PCR identification of T. whipplei confirmed the disease. The patient was initially treated with intravenous ceftriaxone, followed by oral trimethoprim/sulfamethoxazole with significant clinical improvement.

Conclusions

This case is reported due to its rarity and the diagnostic challenge it presents. Although uncommon, Whipple's disease should be considered as a differential diagnosis of malabsorption syndrome due to its systemic impact and possible treatment with targeted antibiotic therapy.

An atypical case of Whipple's disease presenting as fever of unknown origin: A brief review

A 59-year-old woman with epilepsy was admitted to hospital with a 6-year history of fever of unknown origin (FUO). Computed tomography (CT) showed extensive low-attenuation mesenteric and retroperitoneal lymphadenopathy. Investigations for malignancy and infection were negative, including two separate excisional biopsies of lymph nodes. An ascending aortic aneurysm was seen on CT, and a diagnosis of large vessel vasculitis (LVV) was considered. A trial of prednisone for presumed LVV was initiated and then discontinued when positron emission tomography (PET) failed to show vasculitis. Repeat core biopsy of a mesenteric lymph node revealed non-necrotizing granulomatous inflammation and histiocytes with periodic acid-Schiff (PAS)-positive intracellular material. Electron microscopy and polymerase chain reaction (PCR) of the tissue confirmed Tropheryma whipplei. She was treated with ceftriaxone for 2 weeks, followed by long-term combination doxycycline and hydroxychloroquine. The patient's seizure control improved on therapy, raising the suspicion that the seizure disorder was due to Whipple's disease.

Whipple's disease and Tropheryma whipplei infections: when to suspect them and how to diagnose and treat them

PURPOSE OF REVIEW

The delay between first clinical signs and diagnosis of Whipple's disease and Tropheryma whipplei infections is more than 6 years, and relapses are frequently observed, resulting in a need for clinicians to be aware of this infection.

RECENT FINDINGS

18 FDG-PET is useful in the diagnosis and the follow-up of patients (particularly in case of neurological involvement). Histological involvement remains the goldstandard for classic Whipple's disease diagnosis. PCR performed on biopsies of fluid is the main tool for the diagnosis of localized chronic infections. PCR performed on urine samples should become an important role of noninvasive diagnostic strategies, while T. whipplei PCR performed on saliva and stool lack specificity. Because of lifetime susceptibility to T. whipplei and in-vitro susceptibility data, a 1-year course of doxycycline and hydroxychloroquine followed by a lifelong treatment by doxycycline is recommended for Whipple's disease, localized endocarditis and encephalitis.

SUMMARY

Clinical involvement of the different T. whipplei infections is well described, as well as the treatment of Whipple's disease, endocarditis and encephalitis. The place of PCR performed on urine remains to be clarified for diagnosis of localized T. whipplei infections and acute infections as well as the optimal treatment for arthritis and acute infections.

Whipple's Disease Affecting Ileal Peyer's Patches: The First Case Report

Whipple's disease is a rare chronic systemic bacterial infectious disease which can affect multiple organs, with a wide clinical spectrum encompassing many symptoms presenting in various forms and combinations. In the cases where the gastrointestinal tract is implicated, the more frequent localizations involve the small bowel, especially the duodenum. A case of a 67-year-old man who underwent clinical investigation after presenting with a progressive weight loss and showing a hypercapting right paracoeliac adenopathy at PET-CT scan is reported herein. A gastroscopy and a colonoscopy were done. The biopsies of the endoscopically normal ileal mucosa encompassed some submucosal Peyer's patches. Histological examination of this lymphoid tissue revealed several foamy macrophages which turned out positive on periodic acid-Schiff special staining. Polymerase chain reaction of the microdissected lymph follicles allowed for confirming Whipple's disease diagnosis. A targeted antibiotic treatment administrated to the patient led to a rapid clinical improvement. This finding of a previously unreported localization of infected macrophages in Whipple's disease suggests that sampling the organized mucosal-submucosal lymphoid tissue may increase the diagnostic yield in endoscopic biopsies.

Tropheryma whipplei intestinal colonization in Italian and migrant population: a retrospective observational study

AIM

To obtain the first molecular epidemiological survey of Tropheryma whipplei intestinal colonization in Italy. Materials & methods: Retrospective, observational study to assess the prevalence of T. whipplei, the causative agent of Whipple's disease, in stool samples (real-time PCR) of patients attending the Center for Tropical Diseases (Italy) and risk factors associated.

RESULTS

Overall prevalence was 6.9% (85/1240). The younger age group showed a significantly higher rate than older age group (12.7 vs 5.9%, p = 0.002). The prevalence was 4.9% for Italians and 9.3% for migrants (p = 0.003). Among the latter, children less than 10 years had higher prevalence than older ones (17.3 vs 7.3%, p = 0.003). The young age, male gender and Giardia duodenalis and Entamoeba histolytica coinfection were risk factors.

CONCLUSION

Our study confirms an increased risk of acquiring T. whipplei infection during childhood, under poor sanitary conditions.

Peripheral-blood b-cell subset disturbances in inflammatory joint diseases induced by Tropheryma whipplei

Objective

To look for abnormalities in circulating B-cell subsets in patients with rheumatic symptoms of Whipple’s disease (WD).

Method

Consecutive patients seen between 2010 and 2016 for suspected inflammatory joint disease were identified retrospectively. Results of standardized immunological and serological tests and of peripheral-blood B-cell and T-cell subset analysis by flow cytometry were collected. Patients with criteria suggesting WD underwent PCR testing for Tropheryma whipplei, and those with diagnosis of WD (cases) were compared to those without diagnosis (controls). We used ROC curve analysis to evaluate the diagnostic value of flow cytometry findings for WD.

Results

Among 2917 patients seen for suspected inflammatory joint disease, 121 had suspected WD, including 9 (9/121, 7.4%) confirmed WD. Proportions of T cells and NK cells were similar between suspected and confirmed WD, whereas cases had a lower proportion of circulating memory B cells (IgD^-CD38^low, 18.0%±9.7% vs. 26.0%±14.2%, P = 0.041) and higher ratio of activated B cells over memory B cells (4.4±2.0 vs. 2.9±2.2, P = 0.023). Among peripheral-blood B-cells, the proportion of IgD+CD27- naive B cells was higher (66.2%±18.2% vs. 54.6%±18.4%, P = 0.047) and that of IgD-CD27+ switched memory B cells lower (13.3%±5.7% vs. 21.4%±11.9%, P = 0.023), in cases vs. controls. The criterion with the best diagnostic performance was a proportion of IgD+CD27- naive B cells above 70.5%, which had 73% sensitivity and 80% specificity.

Conclusion

Our study provides data on peripheral-blood B-cell disturbances that may have implications for the diagnosis and pathogenetic understanding of WD.

Tropheryma whipplei Infection (Whipple Disease) in the USA

BACKGROUND

Whipple disease (WD) is an infection caused by the bacterium Tropheryma whipplei (TW). Few cases have been reported in the USA.

AIMS

To report on the demographics, clinical manifestations, diagnostic findings, treatment, and outcomes of TW infection.

METHODS

Cases of TW infection diagnosed from 1995 to 2010 were identified in three US referral centers and from 1995 to 2015 in one. Definite classic WD was defined by positive periodic acid-Schiff (PAS) staining and probable WD by specific positive TW polymerase chain reaction (PCR) of intestinal specimens. Localized infections were defined by a positive TW PCR result from samples of other tissues/body fluids.

RESULTS

Among the 33 cases of TW infections, 27 (82%) were male. Median age at diagnosis was 53 years (range 11-75). Diagnosis was supported by a positive TW PCR in 29 (88%) and/or a positive PAS in 16 (48%) patients. Classic WD was the most frequent presentation (n = 18, 55%), with 14 definite and 4 probable cases. Localized infections (n = 15, 45%) affected the central nervous system (n = 7), joints (n = 4), heart (n = 2), eye (n = 1), and skeletal muscle (n = 1). Blood PCR was negative in 9 of 17 (53%) cases at diagnosis. Ceftriaxone intravenously followed by trimethoprim and sulfamethoxazole orally was the most common regimen (n = 23, 70%). Antibiotic therapy resulted in clinical response in 24 (73%).

CONCLUSIONS

TW infection can present as intestinal or localized disease. Negative small bowel PAS and PCR do not exclude the diagnosis of TW infection, and blood PCR is insensitive for active infection.

Fluorescent in situ hybridization can be used as a complementary assay for the diagnosis of Tropheryma whipplei infection

BACKGROUND

Immunohistochemistry and Periodic acid-Schiff (PAS) staining have been routinely used for the diagnosis of Whipple's disease (WD). However, these methods present limitations. As a result, the last years, Fluorescence in situ hybridization (FISH) has been increasingly used as a complementary tool for the diagnosis of WD from various tissue samples.

CASE REPORT

In this study, we visualized, by FISH, Tropheryma whipplei within macrophages of a lymph node from a patient with WD. Moreover, we report in this study a patient with a pulmonary biopsy compatible with WD by PAS, immunostaining and FISH, although the specific molecular assays for T. whipplei were negative. Sequencing analysis of the 16S rDNA revealed a T. whipplei-related species with unknown classification.

CONCLUSION

FISH can be a valuable method for the detection of Tropheryma species in formalin-fixed paraffin-embedded tissues. FISH cannot replace the other already approved diagnostic techniques for WD, it can be used as a complementary tool and can provide supplementary information in a relatively short time.

Ocular Whipple Disease: Report of Three Cases

Purpose: To emphasize the different manifestations of ocular involvement in Whipple disease with challenge in establishing the diagnosis as clinical, laboratory, and histological features could mimic other uveitis entities. Methods: Case reports of three patients. Results: The first patient was an African male suffering from a chronic bilateral keratoconjunctitivitis that was initially misdiagnosed as a chronic allergic conjunctivitis. The second patient was an Italian female who presented with bilateral vitritis, whereas the third patient was an Italian male suffering from a chronic bilateral panuveitis. The diagnosis of ocular Whipple in the first and third case was made by a positive T. whipplei PCR from the ocular specimen, and the second patient had detection of T. whipplei from extraocular sites. Conclusions: Whipple disease can have protean manifestations in the eye including an isolated ocular surface involvement manifested as keratitis.

Mesenteric lymphadenitis as a presenting feature of Whipple's disease: Value of PCR analysis

Whipple's disease (WD) is a rare chronic and systemic infection caused by the ubiquitous actinomycete Tropheryma whipplei. A case of localized infection with mesenteric adenopathy associated with a prolonged unexplained fever is reported herein. Screening by PCR on saliva and stool was positive, and T. whipplei was formally identified by specific PCR on duodenal and mesenteric adenopathy biopsies. Histological analysis did not demonstrate periodic acid-Schiff-positive macrophages or positive T. whipplei immunochemistry in either the duodenal mucosa or mesenteric nodes. Treatment with hydroxychloroquine and doxycycline allowed a rapid resolution of symptoms, and subsequent saliva and stool PCR results were negative.

Usefulness of polymerase chain reaction for diagnosing Whipple's disease in rheumatology

Objectives

To determine when Tropheryma whipplei polymerase chain reaction (PCR) is appropriate in patients evaluated for rheumatological symptoms.

Methods

In a retrospective observational study done in rheumatology units of five hospitals, we assessed the clinical and radiological signs that prompted T. whipplei PCR testing between 2010 and 2014, the proportion of patients diagnosed with Whipple’s disease, the number of tests performed and the number of diagnoses according to the number of tests, the patterns of Whipple’s disease, and the treatments used. Diagnostic ascertainment was based on 1- Presence of at least one suggestive clinical finding; 2- at least one positive PCR test, and 3- a response to antibiotic therapy described by the physician as dramatic, including normalization of C Reactive Protein.

Results

At least one PCR test was performed in each of 267 patients. Rheumatic signs were peripheral arthralgia (n = 239, 89%), peripheral arthritis (n = 173, 65%), and inflammatory back pain (n = 85, 32%). Whipple’s disease was diagnosed in 13 patients (4.9%). The more frequently positive tests were saliva and stool. In the centres with no diagnoses of Whipple’s disease, arthritis was less common and constitutional symptoms more common. The group with Whipple’s disease had a higher proportion of males, older age, and greater frequency of arthritis. The annual incidence ranged across centres from 0 to 3.6/100000 inhabitants.

Conclusion

Males aged 40–75 years with unexplained intermittent seronegative peripheral polyarthritis, including those without constitutional symptoms, should have T. whipplei PCR tests on saliva, stool and, if possible, joint fluid.

Limbic encephalitis as a relapse of Whipple's disease with digestive involvement and spondylodiscitis

INTRODUCTION

Many clinical manifestations can be related to Tropheryma whipplei infection.

CASE REPORT

We report a Tropheryma whipplei limbic encephalitis developed as a relapse of classical Whipple's disease.

DISCUSSION

This case is to the best of our knowledge the first proof of the effective brain-blood barrier crossing of both doxycycline and hydroxychloroquine as demonstrated by direct concentration monitoring on brain biopsy.

Many More Microbes in Humans: Enlarging the Microbiome Repertoire

The proportion of cultured microorganisms is dramatically lower than those predicted to be involved in colonization, acute, or chronic infections. We report our laboratory's contribution to promoting culture methods. As a result of using culturomics in our clinical microbiology laboratories (including amoeba co-culture and shell-vial culture) and through the use of matrix-assisted laser desorption/ionization-time-of-flight and the 16S rRNA gene for identification, we cultured 329 new bacterial species. This is also the first time that 327 of species have been isolated from humans, increasing the known human bacterial repertoire by 29%. We isolated 4 archaeal species for the first time from human, including 2 new species. Of the 100 isolates of giant viruses, we demonstrated the human pathogenicity of Mimivirus in pneumonia and Marseillevirus in diverse clinical situations. From sand flies, we isolated most of the known Phlebovirus strains that potentially cause human infections. Increasing the repertoire of human-associated microorganisms through culture will allow us to test pathogenicity models with viable microorganisms.

From Expert Protocols to Standardized Management of Infectious Diseases

We report here 4 examples of management of infectious diseases (IDs) at the University Hospital Institute Méditerranée Infection in Marseille, France, to illustrate the value of expert protocols feeding standardized management of IDs. First, we describe our experience on Q fever and Tropheryma whipplei infection management based on in vitro data and clinical outcome. Second, we describe our management-based approach for the treatment of infective endocarditis, leading to a strong reduction of mortality rate. Third, we report our use of fecal microbiota transplantation to face severe Clostridium difficile infections and to perform decolonization of patients colonized by emerging highly resistant bacteria. Finally, we present the standardized management of the main acute infections in patients admitted in the emergency department, promoting antibiotics by oral route, checking compliance with the protocol, and avoiding the unnecessary use of intravenous and urinary tract catheters. Overall, the standardization of the management is the keystone to reduce both mortality and morbidity related to IDs.

IRF4 haploinsufficiency in a family with Whipple's disease

Most humans are exposed to Tropheryma whipplei (Tw). Whipple's disease (WD) strikes only a small minority of individuals infected with Tw (<0.01%), whereas asymptomatic chronic carriage is more common (<25%). We studied a multiplex kindred, containing four WD patients and five healthy Tw chronic carriers. We hypothesized that WD displays autosomal dominant (AD) inheritance, with age-dependent incomplete penetrance. We identified a single very rare non-synonymous mutation in the four patients: the private R98W variant of IRF4, a transcription factor involved in immunity. The five Tw carriers were younger, and also heterozygous for R98W. We found that R98W was loss-of-function, modified the transcriptome of heterozygous leukocytes following Tw stimulation, and was not dominant-negative. We also found that only six of the other 153 known non-synonymous IRF4 variants were loss-of-function. Finally, we found that IRF4 had evolved under purifying selection. AD IRF4 deficiency can underlie WD by haploinsufficiency, with age-dependent incomplete penetrance.