Derangements of lacrimal drainage-associated lymphoid tissue (LDALT) in human chronic dacryocystitis

Etiopathogenesis of primary acquired nasolacrimal duct obstruction (PANDO)

Primary acquired nasolacrimal duct obstruction, or PANDO, is a common adult lacrimal drainage disorder. The current treatment modality of dacryocystorhinostomy to bypass the obstructed nasolacrimal duct has excellent outcomes. However, the understanding of the disease etiopathogenesis needs to be revisited. There are not many studies that specifically assessed any hypothesis or ones that convincingly put forth the presumed or confirmed interpretations regarding the PANDO pathogenesis or the mechanisms or pathways involved therein. Histopathological evidence points to recurrent inflammation of the nasolacrimal duct, subsequent fibrosis, and the resultant obstruction. The disease etiopathogenesis is considered multifactorial. Several implicated suspects include anatomical narrowing of the bony nasolacrimal duct, vascular factors, local hormonal imbalance, microbial influence, nasal abnormalities, autonomic dysregulation, surfactants, lysosomal dysfunction, gastroesophageal reflux, tear proteins, and deranged local host defenses. The present work reviewed the literature on the etiopathogenesis of primary acquired nasolacrimal duct obstruction (PANDO) to gain insights into the present state of the understanding and the high-value translational implications of precisely decoding the disease etiology.

Balloon Dacryocystoplasty with Pushed Monocanalicular Intubation as a Primary Management for Primary Acquired Nasolacrimal Duct Obstruction

Given the improvement in the instrument and techniques, novel surgical interventions emerged to avoid the osteotomy from the gold standard dacryocystorhinostomy (DCR) for treating primary acquired nasolacrimal duct obstruction (PANDO). This study's aim is to compare the surgical outcomes of antegrade balloon dacryocystoplasty (DCP) with pushed monocanalicular intubation (MCI) to balloon DCP alone in patients with complete PANDO. Adult patients with complete PANDO receiving balloon DCP followed by pushed MCI or balloon DCP alone from December 2014 to May 2019 were retrospectively reviewed. A total of 37 eyes of 29 patients were treated with balloon DCP with pushed MCI for 1 month, whereas 35 eyes of 28 patients were treated with balloon DCP alone. The success rates at 1 month, 3 months, and 6 months after operation were 89.2%, 73.0%, and 70.2%, respectively, in balloon DCP with MCI group, and 62.9%, 62.9%, and 60.0%, respectively, in the balloon DCP alone group. The balloon DCP with pushed MCI group had a better success rate but only reached statistical significance at 1 month postoperatively (p < 0.01). Subgroup analysis was performed based on age. The success rate in those under 65 in the combined balloon DCP with MCI group was significantly higher than in balloon DCP alone group (72.7% vs. 9.1%, p = 0.004), whereas there was no significant difference between those aged at least 65 in the combined group and the balloon DCP alone group (69.2% vs. 83.3%, p = 0.2). Conclusively, there was no significant difference in the success rate between antegrade balloon DCP with and without pushed MCI in general. Nevertheless, the former procedure was associated with significantly higher surgical success rate than the latter in younger patients.

SARS-CoV-2 infection augments species- and age-specific predispositions in cotton rats

Heterogeneity of COVID-19 manifestations in human population is vast, for reasons unknown. Cotton rats are a clinically relevant small animal model of human respiratory viral infections. Here, we demonstrate for the first time that SARS-CoV-2 infection in cotton rats affects multiple organs and systems, targeting species- and age-specific biological processes. Infection of S. fulviventer, which developed a neutralizing antibody response and were more susceptible to SARS-CoV-2 replication in the upper respiratory tract, was accompanied by hyperplasia of lacrimal drainage-associated lymphoid tissue (LDALT), a first known report of mucosa-associated lymphoid tissue activation at the portal of SARS-CoV-2 entry. Although less permissive to viral replication, S. hispidus showed hyperplasia of bone marrow in the facial bones and increased pulmonary thrombosis in aged males. Augmentation of these features by SARS-CoV-2 infection suggests a virus-induced breach in regulatory mechanisms which could be devastating for people of all ages with underlying conditions and in particular for elderly with a multitude of ongoing disorders.

[The role of miRNA in the pathogenesis of diseases associated with functional dysregulation of the lacrimal gland]

At this time, the mechanism causing lacrimal gland dysfunction is not understood completely. In diseases associated with lacrimal gland involvement (Sjogren's syndrome, sarcoidosis, IgG4-associated disease, etc.) patients have been observed to experience elevated cellular apoptosis, active production of autoantibodies to glandular tissue, increased level of pro-inflammatory cytokines, functional disruption of signaling molecules leading to changes in tear production. Difficulties in differential diagnosis of lacrimal gland dysfunction in above-listed diseases are associated, on the one hand, with similarity of the clinical picture of ophthalmological manifestations, and on the other hand - with complicated morphological interpretation of changes in the glandular tissues. In this view, miRNA is a promising diagnostic and prognostic marker that would help with differential diagnosis as well as with choosing the treatment tactics. Methods of molecular profiling and identification of "molecular phenotypes" of lacrimal gland and ocular surface damage will allow the use of miRNA as biomarkers and prognostic factors for personalized treatment.

Endoscopic dacryocystorhinostomy with short-term, pushed-type bicanalicular intubation vs. pulled-type monocanalicular intubation for primary acquired nasolacrimal duct obstruction

Dacryocystorhinostomy (DCR) has been a primary treatment for adults with nasolacrimal duct obstruction, while the optimal approach and technique remain controversial. With the advancement of endoscopic DCR and the silicone stents, an update of the surgical outcomes and preferable approaches is required. This study aims at comparing the surgical outcomes of endoscopic DCR using pushed bicanalicular intubation (BCI) to pulled monocanalicular intubation (MCI) in adults with primary acquired nasolacrimal duct obstruction (PANDO). Forty five eyes of 45 patients were enrolled, including 22 eyes of 22 patients treated with endoscopic DCR with pulled MCI and 23 eyes of 23 patients with pushed BCI from January 2014 to June 2021. The success rates at stent removal, 1 month and 3 months after removal were 95, 91, and 82%, respectively, in the MCI group, and 100, 87, and 87% in the BCI group. The BCI group had better success rates but failed to reach a significant difference (p = 0.49, p = 0.67, p = 0.24, respectively). After analyzing with binary logistic regression, the implant material was demonstrated as the predictive of surgical success (p = 0.045). There was no significant difference in success rates between patients with dacryocystitis and those without dacryocystitis. We conclude that endoscopic DCR with pushed BCI is easily manipulated and has a promising surgical outcome over pulled MCI. Stent indwelling duration as well as history of dacryocystitis have less influence on the success rates.

Differently Expressed Circular RNAs in Lacrimal Sacs From Patients With Chronic Dacryocystitis

This study was designed to identify differently expressed circular RNAs (circRNAs) and investigate their potential roles in lacrimal sacs from patients with chronic dacryocystitis. The lacrimal sac samples of three chronic dacryocystitis patients and three control subjects were collected for RNA sequencing after ribosomal RNA was depleted. Differently expressed circRNAs and messenger RNAs (mRNAs) were used for co-expression analysis. CircRNA-microRNA (miRNA)-mRNA interaction network were also established by miRanda software. Meanwhile, pathway and functional enrichment analysis were conducted for the down- and up-regulated mRNAs in the circRNA-mRNA co-expression network. The expression levels of circRNAs and mRNAs in chronic dacryocystitis and control samples were validated by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). In all the 3,909 circRNAs predicted through RNA sequencing, 25 circRNAs (20 up-regulated and 5 down-regulated) expressed differently in chronic dacryocystitis samples. Besides, there identified 1,486 differentially expressed mRNAs. Of these differently expressed circRNAs and mRNAs, eight were validated by qRT-PCR, including MYH2, DSP, CD27, CCL5, FN1, has_circ_0004792, has_circ_0001062, and has_circ_0115476. Gene Ontology (GO) analysis indicated that the majority of altered mRNAs in this co-expression network were involved in immune system processes and meanwhile Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that these altered expressed mRNAs were also amplified in bacterial invasion of epithelial cells, both of which were thought to be involved in the pathogenesis of chronic dacryocystitis. In the circRNA-miRNA-mRNA interaction network, six circRNAs were found to be related to Th1 and Th2 cell differentiation, which was closely associated with the development of chronic dacryocystitis. This study identified statistically significant differences between circRNAs and mRNAs of lacrimal sac samples of chronic dacryocystitis patients and control individuals and provides novel insight into the regulatory mechanism of circRNAs, miRNAs, and mRNAs in the pathogenesis of chronic dacryocystitis.

Mucosa-Associated Lymphoid Tissue and Tertiary Lymphoid Structures of the Eye and Ear in Laboratory Animals

Mucosa-associated lymphoid tissue (MALT) of special senses is poorly described and can be confused with nonspecific mononuclear cell infiltrates and tertiary lymphoid structures (TLS). In the eye, MALT consists mostly of conjunctiva-associated lymphoid tissue (CALT) and lacrimal drainage-associated lymphoid tissue (LDALT). In humans, CALT and LDALT are important components of the normal eye-associated lymphoid tissue (EALT), but EALT is less frequently described in ocular tissues of animals. The EALT are acquired postnatally in preferential mucosal sites, expand with antigenic exposure, form well-developed lymphoid follicles, and are reported to senesce. Lymphoid follicles that are induced concurrently with chronic inflammation are more appropriately considered TLS but must be differentiated from inflammation in MALT. Less understood is the etiology for formation of lymphoid tissue aggregates in the ciliary body, limbus, or choroid of healthy eyes in animals and humans. In the healthy eustachian tube and middle ear of animals and humans, MALT may be present but is infrequently described. Concurrent with otitis media, lymphoid follicles in the eustachian tube are probably expanded MALT, but lymphoid follicles in the middle ear may be TLS. The purpose of this comparative review is to familiarize toxicologic pathologists with MALT in the special senses and to provide considerations for differentiating and reporting eye and ear MALT from immune or inflammatory cell infiltrates or inflammation in nonclinical studies, and the circumstances for reporting TLS in compartments of the eye and ear.

Lymphoproliferative tumors involving the lacrimal drainage system: a major review

PURPOSE

To provide a literature review on lymphoproliferative lesions involving the lacrimal drainage system.

METHODS

The authors performed a pubmed search of all articles published in English on lymphoma/leukemia of lacrimal sac and the nasolacrimal duct. Data analyzed include prevalence, demographics, clinical presentations, treatment outcomes of primary versus secondary lacrimal involvement, and recurrence rates.

RESULTS

Lymphoma/leukemia of lacrimal sac presented at a mean age of 55 years. The majority of the tumors (63%) were primary involvement of lacrimal sac, bilateral involvement being more common in secondary than primary lacrimal sac lymphoma. Epiphora (96%, 98/102), swelling in the lacrimal sac region (75%, 77/102), and acute dacryocystitis (31%) were the most frequent presenting features. Thirty-six percent of the lesions were diagnosed incidentally while performing a dacryocystorhinostomy (DCR). Among primary sac lymphomas, diffuse large B-cell lymphoma (DLBCL) (43%) was the most common sub-type followed by MALToma (24%), unclassified B-cell lymphoma (21%), lymphoid hyperplasia (5%) and 3% each small lymphocytic lymphoma (SLL) and NK/T cell lymphoma. Management usually involves chemotherapy and/ or radiotherapy with or without surgical resection. Successful outcomes in terms of local disease control could be achieved in all the cases; however, 15% died of the systemic disease after a mean 18 months from the time of sac involvement. Aggressive lymphomas like NK/T-cell have the worst prognosis.

CONCLUSION

Lymphoproliferative involvement of lacrimal sac has a high incidence of acute dacryocystitis with a good response to chemotherapy. Epiphora in patients with leukemia/lymphoma should arouse suspicion of a lacrimal drainage involvement.

Etiopathogenesis of Primary Acquired Nasolacrimal Duct Obstruction: What We Know and What We Need to Know

PURPOSE

To provide a systematic review of the literature on the etiopathogenesis of primary acquired nasolacrimal duct obstruction (PANDO).

METHODS

The authors performed a PubMed search of all articles published in English with specific reference to etiopathogenesis of PANDO or associations of PANDO. Data captured include demographics, study techniques, hypothesis, presumed or confirmed interpretations with regards to pathogenesis, mechanisms, or pathways. Specific emphasis was laid on addressing the lacunae and potential directions for future research.

RESULTS

Numerous factors are believed to contribute to the etiopathogenesis of PANDO. The basic pathogenesis involves inflammation, vascular congestion, mucosal edema, fibrosis, obstruction, and stasis. Bony nasolacrimal duct diameter does not appear to play a significant role. There is no convincing data to substantiate nose as the site of disease origin and nasal factors appear to be comorbidities. Hormonal mechanisms are more evidence-based but can only partly explain the pathogenesis. Vascular theories are based on the behavior of perilacrimal cavernous bodies, their autonomic control, and additional structural changes in the helical patterns of connective tissue fiber arrangements. Repeated vascular malfunction leading to structural epithelial and subepithelial changes currently appears to be the most evidence-based and accepted theory. Tear proteomics holds a promise in decoding the etiopathogenesis of PANDO, at least in part.

CONCLUSIONS

The etiopathogenesis of PANDO appears to be multifactorial. Hormonal microenvironments, vascular factors, and tear proteomics are promising candidates for further work. There is a need for focused work by Clinician-Scientists and the answers can have far reaching clinical implications.

Viral nucleic acid analysis with PCR in lacrimal tissue and nasal swab samples of primary acquired nasolacrimal duct obstruction cases

PURPOSE

To evaluate the role of viral infections in the pathogenesis of primary acquired nasolacrimal duct obstruction.

METHODS

The study included 48 patients diagnosed with primary acquired nasolacrimal duct obstruction undergoing dacryocystorhinostomy surgery. Prior to dacryocystorhinostomy surgery, nasal swab sample was taken from the inferior meatus at the same side. During dacryocystorhinostomy, tissue biopsy sample (2 × 2 mm) was taken from the junction area of the lacrimal sac and nasolacrimal duct. Following nucleic acid extraction, polymerase chain reaction was performed.

RESULTS

The patients consisted of 9 (18.8%) men and 39 (81.2%) women with a mean age of 51.0 ± 14.3 years. Qualitative polymerase chain reaction showed viral genome in the nasal swabs of 10 (20.8%) patients, including coronavirus 229E (three cases), coronavirus HKU1 (two cases), respiratory syncytial virus (two cases), coronavirus OC43 (one case), coronavirus NL63 (one case), and adenovirus (one case). In the dacryocystorhinostomy samples, viral genomes were detected in four (8.3%) cases, including respiratory syncytial virus (two cases), coronavirus HKU1 (one case), and adenovirus (one case). There was a statistically significant agreement between nasal mucosal swab and dacryocystorhinostomy biopsy samples in terms of respiratory syncytial virus positivity (kappa = 1.000, p = 0.001).

CONCLUSION

Although the viral genome was detected in the samples, a direct relationship between viruses and pathogenesis of primary acquired nasolacrimal duct obstruction could not be revealed because of the low number of positive results. However, considering the profibrotic characteristics of specific viruses such as respiratory syncytial virus and adenovirus, viral infections may be one of the many predisposing factors of primary acquired nasolacrimal duct obstruction.

A Rare Complication of Oropharyngeal Tularemia: Dacryocystitis

Tularemia is a zoonotic disease caused by Francisella tularensis, a highly virulent gram-negative coccobacillus. Oropharyngeal tularemia, one of the clinical subtypes, is the most common clinical form of the disease in Eastern Europe, including Turkey. This clinical form affects mostly the head and neck region and the most common complaints of patients are mass in the neck, sore throat, and fever. This form of tularemia may be confused with tonsillitis, pharyngitis, or cervical lymphadenitis caused by other microbial agents due to the nonspecific clinical and laboratory features. In this study, we present a patient with nasolacrimal duct obstruction and dacryocystitis caused by oropharyngeal tularemia.

Relationship between lacrimal sac size and duration of tearing in nasolacrimal duct obstruction

OBJECTIVE

To analyze the relationship among the presence of lacrimal sac mucus retention, the vertical size of the lacrimal sac, and the duration of tearing symptom in patients with nasolacrimal duct obstruction (NLDO).

DESIGN

Retrospective case series.

PARTICIPANTS

We reviewed the medical records of 473 patients (664 eyes) who underwent external dacryocystorhinostomy for primary NLDO.

METHODS

The information about the presence of lacrimal sac mucus retention and vertical size of the lacrimal sac lumen was collected intraoperatively. The vertical size of the lacrimal sac was classified into 3 groups: small (<5 mm), medium (5-10 mm), and large (>10 mm). The relationship between the lacrimal sac size, presence of mucus retention, and duration of tearing was analyzed.

RESULTS

Of the 664 eyes, 138 had a small lacrimal sac, 199 had a medium lacrimal sac, and 327 had a large lacrimal sac. The distribution of the lacrimal sac size groups differed significantly between the eyes with (n = 245) and without (n = 419) mucus retention (p < 0.001). Among all the subjects of each lacrimal sac size group, there was no significant difference in the duration of symptoms (p = 0.176). However, in patients without mucus retention, the symptom duration in the small lacrimal sac group was significantly longer than that in the large lacrimal sac group (p = 0.017).

CONCLUSIONS

In cases with mucus retention, a small lacrimal sac is rare. In cases without mucus retention, the duration of tearing symptom was significantly longer in small lacrimal sac group.

Co-localization of lymphoid aggregates and lymphatic networks in nose- (NALT) and lacrimal duct-associated lymphoid tissue (LDALT) of mice

Background

The lymphatic vascular pattern in the head of mice has rarely been studied, due to problems of sectioning and immunostaining of complex bony structures. Therefore, the association of head lymphoid tissues with the lymphatics has remained unknown although the mouse is the most often used species in immunology.

Results

Here, we studied the association of nasal and nasolacrimal duct lymphatics with lymphoid aggregates in 14-day-old and 2-month-old mice. We performed paraffin sectioning of whole, decalcified heads, and immunostaining with the lymphatic endothelial cell-specific antibodies Lyve-1 and Podoplanin. Most parts of the nasal mucous membrane do not contain any lymphatics. Only the region of the inferior turbinates contains lymphatic networks, which are connected to those of the palatine. Nose-associated lymphoid tissue (NALT) is restricted to the basal parts of the nose, which contain lymphatics. NALT is continued occipitally and can be found at both sides along the sphenoidal sinus, again in close association with lymphatic networks. Nasal lymphatics are connected to those of the ocular region via a lymphatic network along the nasolacrimal duct (NLD). By this means, lacrimal duct-associated lymphoid tissue (LDALT) has a dense supply with lymphatics.

Conclusions

NALT and LDALT play a key role in the immune system of the mouse head, where they function as primary recognition sites for antigens. Using the dense lymphatic networks along the NLD described in this study, these antigens reach lymphatics near the palatine and are further drained to lymph nodes of the head and neck region.

NALT and LDALT develop in immediate vicinity of lymphatic vessels. Therefore, we suggest a causative connection of lymphatic vessels and the development of lymphoid tissues.

Successful treatment of methicillin-resistant Staphylococcus aureus infection associated with Jones tube using vancomycin eye drops and rifampicin

OBJECTIVE

Complications associated with the lacrimal Lester Jones tube have been reported. The infections associated with the tube and proper treatment are not well known. The authors have introduced a successful treatment regimen for persistent methicillin-resistant Staphylococcus aureus (MRSA) periocular infection associated with the lacrimal Lester Jones tube without tube removal.

DESIGN

Retrospective case series.

PARTICIPANTS

Six patients with MRSA infection associated with the Lester Jones tube without tube removal.

METHODS

Four patients had improper tube position with total regurgitation and 2 patients had relative normal tube position with a partial to normal passage, but the tube tip irritated the nasal mucosa wound persistently. In all 6 cases, development of a biofilm on the tube was observed. All cultures were positive for MRSA.

RESULTS

All patients were prescribed a combination therapy of topical ocular vancomycin and oral rifampicin before or after the dislocated tube reposition. Periocular symptoms resolved within 1 week, and the biofilm on the tube was gradually reduced during combination therapy. Signs of recurrence of infection were not noted during the follow-up visits.

CONCLUSION

Patients showing infection signs associated with the Jones tube need to be examined before complete removal of the infected tube. Medical treatment with vancomycin eye drops combined with oral rifampicin for persistent MRSA infection associated with the Lester Jones tube produced a successful result. Removal of the biofilm on the tube at follow-up visits is important to prevent micro-organisms from dispersing around the tissue. If the Jones tube is dislocated, repositioning is highly recommended to prevent periocular MRSA infection recurrence.

Primary Marginal Zone B-Cell Lymphoma of the Mucosa-Associated Lymphoid Tissue of the Lacrimal Sac Found with Epiphora: A Case Report

We report a case of a primary marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue of the lacrimal sac, which was found in a patient with epiphora without palpable mass. Magnetic resonance imaging demonstrated mucosal thickening of the lacrimal sac with a patent lumen, consistent with the intraoperative finding. Epiphora resolved, which was confirmed by smooth syringing, 1 month after starting the immunotherapy.

Macrophages and Uveitis in Experimental Animal Models

Resident and infiltrated macrophages play relevant roles in uveitis as effectors of innate immunity and inductors of acquired immunity. They are major effectors of tissue damage in uveitis and are also considered to be potent antigen-presenting cells. In the last few years, experimental animal models of uveitis have enabled us to enhance our understanding of the leading role of macrophages in eye inflammation processes, including macrophage polarization in experimental autoimmune uveoretinitis and the major role of Toll-like receptor 4 in endotoxin-induced uveitis. This improved knowledge should guide advantageous iterative research to establish mechanisms and possible therapeutic targets for human uveitis resolution.

Dacryocystectomy: goals, indications, techniques and complications

Dacryocystectomy is a well-established oculo plastics procedure that refers to a complete surgical extirpation of the lacrimal sac. It was first described by Woolhouse in 1724 and was the standard of care before the advent of dacryocystorhinostomy for management of dacryocystitis and lacrimal fistulas. Although it is a seldom performed procedure worldwide, it still has its place in the surgical armamentarium for certain specific indications like malignant lacrimal sac tumors. It is almost always performed through an external skin incision except in certain exceptional circumstances where endoscopic dacryocystectomy may be needed. This article discusses the indications, goals, techniques, and complications of a dacryocystectomy.