Visual Loss Associated with Rickettsial Disease

Vascular Changes in Eyes with Post-Fever Retinitis Pre and Post Treatment Demonstrated Using Optical Coherence Tomography Angiography

PURPOSE

To document vascular changes in eyes with post-fever retinitis (PFR) pre and post treatment demonstrated using optical coherence tomography angiography (OCTA).

METHODS

This is a retrospective observational case series wherein patients with PFR were retrospectively evaluated for changes in the retinal vasculature during the course of disease using OCTA.

RESULTS

At presentation, OCTA revealed flow void areas in superficial and deep capillary plexus (SCP and DCP) corresponding to the areas of retinitis. Post treatment, OCTA showed a significant decrease in the flow void areas with the appearance of new capillary network in both SCP and DCP. The optical coherence tomography also demonstrated normalization of retinal architecture over time. It is speculated that the good visual outcome in PFR could be attributed to the normalization of retinal architecture and remodelling in retinal vasculature.

CONCLUSION

OCTA being non-invasive can be used to understand and quantify the extent of vascular remodelling in PFR.

Sea-fan retinal neovascularization associated with rickettsial retinitis: a case report

BACKGROUND

Rickettsial disease has been commonly associated with retinitis, retinal vasculitis, and optic nerve involvement, but the development of retinal neovascularization has been very rarely reported. We herein describe a case of rickettsial retinitis complicated with the development of sea-fan retinal neovascularization documented with multimodal imaging, including fundus photography, SS-OCT, fluorescein angiography, and SS-OCT angiography.

CASE PRESENTATION

A 26-year-old female with a history of fever one week earlier presented with sudden decreased vision in the left eye. Best-corrected visual acuity (BCVA) was 20/2000 and the patient was diagnosed with rickettsial retinitis along the superotemporal retinal vascular arcade associated with serous retinal detachment and retinal hard exudates. The indirect immunofluorescence test was positive for Rickettsia conorii, and the patient was treated with oral doxycycline (200 mg/day) and oral prednisone (0.75 mg/kg/day, with gradual tapering). Four weeks after presentation, the retinal infiltrate and associated serous retinal detachment had resolved, but retinal hard exudates had increased. A large sea-fan preretinal fibrovascular neovascularization became apparent along the superotemporal retinal vascular arcade, but there was no associated retinal ischemia on fluorescein angiography. The patient received an adjunctive single intravitreal injection of 1.25 bevacizumab. Sequential follow-up examinations showed shrinking of sea-fan retinal neovascularization, a complete resolution of retinal hard exudates, and the development of a self-limited vitreous hemorrhage. On last follow-up, 30 months after intravitreal bevacizumab injection, BCVA was 20/25.

CONCLUSION

Patients with rickettsial retinitis may develop a sea-fan retinal neovascularization, with subsequent vitreous hemorrhage, putatively through inflammatory mechanisms. Multimodal imaging including OCT, fluorescein angiography, and OCT-angiography, is highly useful for accurate diagnosis and reliable monitoring of the evolution of retinitis, retinal neovascularization, and other retinal changes. The use of a combination therapy with oral doxycycline and corticosteroids and intravitreal anti-VEGF can improve outcomes.

Optical Coherence Tomography and Optical Coherence Tomography Angiography in Neglected Diseases

A group of self-limiting and frequently neglected diseases exist in the literature like Rickettsial disease, Malaria, Dengue fever, Chikungunya, West Nile virus infection, Rift Valley fever, Bartonellosis, or Lyme disease which are poorly understood due to lack of proper diagnostic testing. Currently, multimodal imaging has become a critical modality in the diagnosis and management of ocular diseases. Optical coherence tomography (OCT) is one such remarkable imaging modality in the field of ophthalmology providing high-resolution, cross-sectional images of the retina and choroid with the recent advances such as enhanced depth imaging and swept source OCT. Additionally, OCT angiography (OCTA) has further revolutionised dynamic imaging of retinal and choroidal vasculature non-invasively. This review article highlights the OCT and OCTA biomarkers in the diagnosis and prognosis of the aforementioned neglected diseases.

Treatment Outcomes of Presumed Rickettsial Retinitis: Evidence from OCTA Based Quantitative Analysis

AIM

To quantify retinal ischemia following presumed rickettsial retinitis (RR). To compare outcomes between initial treatment with Doxycycline (Group 1) versus steroids (Group 2).

METHODS

Retrospective analysis of patients with presumed RR was done. ImageJ software was used to obtain %area of ischemia on swept-source optical coherence tomography angiography (SS-OCTA).

RESULTS

Eleven eyes of 8 patients belonged to Group1 and 6 eyes of 3 patients belonged to Group 2. The BCVA improved from logMAR 0.8 ∓ 0.7 to logMAR 0.06 ∓ 0.08 (p < 0.002) and central foveal thickness (CFT) changed from 479μ ∓ 341.3μ to 163.5μ ∓ 20.5μ (p < 0.005) after a median of 5 weeks in Group 1. In Group 2, BCVA improved from logMAR 1.03 ∓ 0.05 to logMAR 0.23 ∓ 0.23 (p < 0.004) and CFT changed from 286.5μ ∓ 158.8μ to 177.5μ ∓ 25.9μ (>0.05) following a mean of 11 weeks. Mean %area of ischemia was 4.6 ∓ 1.5 in Group 1 and 13.9 ∓ 4.1 in Group 2.

CONCLUSION

Analysis of flow deficit on SS-OCTA confirms that treatment with Doxycycline in presumed RR results in less ischemia and quicker recovery than initial treatment with steroids.

Infectious optic neuropathy (ION), how to recognise it and manage it

Optic neuropathy can be of infectious or non-infectious/idiopathic aetiology. Many infectious organisms can cause optic neuropathy that can be of varied presentation including papillitis, retrobulbar optic neuritis, neuroretinitis, and optic perineuritis. Detailed history, ocular, systemic/neurologic examination along with appropriate laboratory evaluation can help clinicians to identify the infectious agent causing optic neuropathy. In spite of recent advanced techniques in serological testing and molecular diagnostics like polymerase chain reaction (PCR), the identification of these pathogens is still a diagnostic challenge. It is ideal to have an infectious disease (ID) consultant in the management team, as most of these infections are multisystem involving diseases. Most infectious agents can be effectively treated with specific antibiotics, with or without corticosteroid therapy, but visual recovery is highly variable and depends entirely on early diagnosis of the causative agent. This review article will provide an overview of common pathogens involved in ION and will describe their management paradigms.

Infectious eye disease in the 21st century-an overview

Infectious diseases affecting the eye often cause unilateral or asymmetric visual loss in children and people of working age. This group of conditions includes viral, bacterial, fungal and parasitic diseases, both common and rare presentations which, in aggregate, may account for a significant portion of the global visual burden. Diagnosis is frequently challenging even in specialist centres, and many disease presentations are highly regional. In an age of globalisation, an understanding of the various modes of transmission and the geographic distribution of infections can be instructive to clinicians. The impact of eye infections on global disability is currently not sufficiently captured in global prevalence studies on visual impairment and blindness, which focus on bilateral disease in the over-50s. Moreover, in many cases it is hard to differentiate between infectious and immune-mediated diseases. Since infectious eye diseases can be preventable and frequently affect younger people, we argue that in future prevalence studies they should be considered as a separate category, including estimates of disability-adjusted life years (DALY) as a measure of overall disease burden. Numbers of ocular infections are uniquely affected by outbreaks as well as endemic transmission, and their control frequently relies on collaborative partnerships that go well beyond the remit of ophthalmology, encompassing domains as various as vaccination, antibiotic development, individual healthcare, vector control, mass drug administration, food supplementation, environmental and food hygiene, epidemiological mapping, and many more. Moreover, the anticipated impacts of global warming, conflict, food poverty, urbanisation and environmental degradation are likely to magnify their importance. While remote telemedicine can be a useful aide in the diagnosis of these conditions in resource-poor areas, enhanced global reporting networks and artificial intelligence systems may ultimately be required for disease surveillance and monitoring.

Hemophagocytic Lymphohistiocytosis (HLH) in Patients with Tick-Borne Illness: A Scoping Review of 98 Cases

Hemophagocytic lymphohistiocytosis (HLH) secondary to tick-borne infections is a rare but potentially life-threatening syndrome. We performed a scoping review according to PRISMA guidelines to systematically analyze the existing literature on the topic. A total of 98 patients were included, with a mean age of 43.7 years, of which 64% were men. Most cases, 31%, were reported from the USA. Immunosuppression was present in 21.4%, with the most common cause being previous solid organ transplantation. Constitutional symptoms were the most common, observed in 83.7% of the patients, while fever was reported in 70.4% of cases. Sepsis was present in 27.6%. The most common laboratory abnormalities in this cohort were thrombocytopenia in 81.6% of patients, while anemia, leukopenia, and leukocytosis were observed in 75.5%, 55.1%, and 10.2%, respectively. Liver enzyme elevation was noted in 63.3% of cases. The H-score was analyzed in 64 patients, with the mean value being 209, and bone marrow analysis was performed in 61.2% of patients. Ehrlichia spp. was the main isolated agent associated with HLH in 45.9%, followed by Rickettsia spp. in 14.3% and Anaplasma phagocytophilum in 12.2%. Notably, no patient with Powassan virus infection or Lyme borreliosis developed HLH. The most common complications were acute kidney injury (AKI) in 35.7% of patients, shock with multiple organ dysfunction in 22.5%, encephalopathy/seizure in 20.4%, respiratory failure in 16.3%, and cardiac complications in 7.1% of patients. Treatment included antibiotic therapy alone in 43.9%, while 5.1% of patients were treated with immunosuppressants alone. Treatment with both antibiotics and immunosuppressants was used in 51% of patients. Appropriate empiric antibiotics were used in 62.2%. In 43.9% of cases of HLH due to tick-borne disease, patients received only antimicrobial therapy, and 88.4% of those recovered completely without the need for immunosuppressive therapy. The mortality rate in our review was 16.3%, and patients who received inappropriate or delayed empiric therapy had a worse outcome. Hence, we suggest empiric antibiotic treatment in patients who are suspected of having HLH due to tick-borne disease or in whom diagnostic uncertainty persists due to diagnostic delay in order to minimize mortality.

Post-fever Retinitis With a Positive Weil-Felix Test: A Study From a Tertiary Center in South India

Background Post-fever retinitis (PFR) is reported two to six weeks after fever and affects one or both eyes. Rickettsial fever is one of the most common causes of PFR. This study aimed to report the clinical features and treatment outcomes of PFR cases with a positive Weil-Felix test. Methodology In this study, we collected demographic data, fever details, eye symptoms, ocular examination findings, optical coherence tomography (OCT) and fundus fluorescein angiography findings, laboratory findings, and length of follow-up of consecutive PFR cases with a positive Weil-Felix test. All cases were treated with oral doxycycline and prednisolone. Final best-corrected visual acuity (BCVA) and ocular examination findings were recorded. Visual field examination and follow-up OCT results were noted if available. Results A total of nine patients (eight males) with a mean age of 39.1 years with fever before ocular symptoms and positive Weil-Felix test were included. Six patients had bilateral disease. The mean initial and final BCVA in the affected eyes was 1.16 and 0.35 logMAR units, respectively (p < 0001). All 15 eyes had typical white retinitis patches and retinal hemorrhages which resolved after treatment. OCT showed hyperreflectivity and inner retinal disorganization over retinitis patches. White subretinal lines were noted in three patients and retinal nerve fiber bundle defect with corresponding visual field defect was seen in one eye. Conclusions In this study, PFR due to rickettsia infections has been reported from our region for the first time. Hence, eye specialists in the region should be aware of this entity.

Every lid swelling is not stye: A rare presentation of scrub typhus eschar

A 17-year-old female patient presented to us with complaints of diffuse swelling in her left upper eyelid with preauricular lymphadenopathy for three days. She was diagnosed with a case of hordeolum externum and was treated on the same line. However, during follow-up, she developed a mild- to moderate-grade fever, which did not subside with treatment. On further investigation, her IgM rapid ELISA for Scrub typhus was positive, which was further confirmed by the Weil-Fellix test (OXK=1:360). She was treated with systemic doxycycline. Within a week, her fever returned to normal baseline, with resolution of local eye lid swelling, and her black scab was also gone. We have reported a case of scrub typhus as a rare manifestation with lid swelling and subsequently eschar formation on the upper eye lid. The patient was promptly treated with oral antibiotics without any morbidity.

Comments on 'Presumed Post-COVID Infection Retinitis - Clinical and Tomographic Features of Retinitis as a Post-COVID Syndrome'

Characteristics and course of known seasonal diseases of pre-coronavirus disease (COVID-19) pandemic era may or may not change during the pandemic. Labelling COVID-19 as a novel etiology for those seasonal diseases or considering it as coinfection is debatable. Appropriate investigations are required to rule out previously known etiologies before correlating it with COVID-19. Epidemic retinitis (ER) or post fever retinitis is one such entity with seasonal variation. Multiple seropositivity for various organisms has been reported for ER during pre-pandemic era. This may significantly increase during the pandemic as the possibility of coinfection with COVID-19 is high. In the absence of gold-standard tests to exclude previously reported causes of ER, one should not undermine the possible coinfection before considering ER as post-COVID-19 syndrome. A study of incidence and pattern of seasonal variation of ER before and during the pandemic is needed before presumptively associating it with COVID-19.

Case Report: Optic neuritis as the initial presentation of Orientia tsutsugamushi infection detected by metagenomic next-generation sequencing

Scrub typhus is an acute febrile illness caused by Orientia tsutsugamushi infection, and typically manifested as fever, eschar, lymphadenopathy, rash, and other flu-like signs. Ocular involvement was not uncommon, and mostly occurred at post-fever or recovery stage in scrub typhus cases. We hereby report a case of scrub typhus presenting as unilateral optic neuritis (ON). A 56-year-old man going wild fishing nearly every day complained of a blurred vision and an inferior visual field defect in the right eye two or three days after an insect-bite like shin induration in his left leg. He was diagnosed as ON, and treated with dexamethasone in the local hospital. Unfortunately, his right eye vision progressively deteriorated during steroid therapy. Three days after steroid therapy ceased, he suffered from a high fever and painful subcutaneous masses in the left groin. Peripheral blood test by metagenomic next-generation sequencing (mNGS) was positive for Orientia tsutsugamushi, but negative for other pathogens. The diagnosis was then revised to scrub typhus and ON. His systemic symptoms rapidly disappeared after oral doxycycline and omadacycline therapy. However, his right eye vision continuously deteriorated to hand motion. Further serum tests for aquaporin 4-IgG antibody and myelin oligodendrocyte glycoprotein-IgG antibody were both negative, but for anticardiolipin IgM and beta-2-glycoprotein-I IgM were both positive. The patient's right eye vision gradually improved after doxycycline combined with steroid pulse therapy. Our case indicates that ON in scrub typhus cases may present as a parainfectious inflammation, and that mNGS is a useful and valuable method for early diagnosis of scrub typhus.

Stepwise approach for fundus imaging in the diagnosis and management of posterior uveitis

An array of retinochoroid imaging modalities aid in comprehensive evaluation of the immunopathological changes in the retina and choroid, forming the core component for the diagnosis and management of inflammatory disorders such as uveitis. The recent technological breakthroughs have led to the development of imaging platforms that can evaluate the layers of retina and choroid and the structural and functional alteration in these tissues. Ophthalmologists heavily rely on imaging modalities such as dye-based angiographies (fluorescein angiography and indocyanine green angiography), optical coherence tomography, fundus autofluorescence, as well as dye-less angiography such as optical coherence tomography angiograph,y for establishing a precise diagnosis and understanding the pathophysiology of the diseases. Furthermore, these tools are now being deployed with a 'multimodal' approach for swift and accurate diagnosis. In this comprehensive review, we outline the imaging platforms used for evaluation of posterior uveitis and discuss the organized, algorithmic approach for the assessment of the disorders. Additionally, we provide an insight into disease-specific characteristic pathological changes and the established strategies to rule out disorders with overlapping features on imaging.

Rickettsia rickettsii infection as an unusual cause of pediatric retinitis: A case report

Purpose

To report a case of infectious pediatric retinitis attributed to Rocky Mountain spotted fever which is rarely reported in the United States.

Observations

A previously healthy 14-year-old male return traveler from Mexico was admitted to the pediatric ICU with septic shock and a diffuse rash. He subsequently complained of blurry vision and was found to have evidence of retinitis on exam. Infectious workup revealed high titers of rickettsial IgM and IgG antibodies. He was treated successfully with 14 days doxycycline and followed up in clinic with improvement in his visual complaints and retinitis.

Conclusions and importance

Rickettsioses are worldwide endemic zoonotic infections caused by Gram negative obligate intracellular bacteria and spread to humans by infected ticks. Rickettsial infections, including Rocky Mountain spotted fever caused by Rickettsia rickettsii, are a cause of infectious retinitis, and atypical and zoonotic infections should remain on the differential diagnosis for patients presenting with rash, systemic illness, and visual complaints, even if the patient's travel or exposure history do not immediately suggest a likely rickettsial infection. In general, the ocular manifestations of rickettsial infection improve with systemic doxycycline treatment of the underlying infection.

Ocular Manifestations of Emerging Arthropod-Borne Infectious Diseases

Purpose

To review the clinical features, diagnosis, treatment modalities, and prognosis of arthropod-borne infectious diseases.

Methods

This is a narrative review on arthropod-borne infectious diseases including general and ophthalmological aspects of these infectious diseases. A comprehensive literature review between January 1983 and September 2020 was conducted in PubMed database. Epidemiology, clinical features, diagnosis, treatment, and prognosis of arthropod-borne infectious diseases were reviewed.

Results

Emergent and resurgent arthropod-borne infectious diseases are major causes of systemic morbidity and death that are expanding worldwide. Among them, bacterial and viral agents including rickettsial disease, West Nile virus, Dengue fever, Chikungunya, Rift valley fever, and Zika virus have been associated with an array of ocular manifestations. These include anterior uveitis, retinitis, chorioretinitis, retinal vasculitis, and optic nerve involvement. Proper clinical diagnosis of any of these infectious diseases is primarily based on epidemiological data, history, systemic symptoms and signs, and the pattern of ocular involvement. The diagnosis is confirmed by laboratory tests. Ocular involvement usually has a self-limited course, but it can result in persistent visual impairment. Doxycycline is the treatment of choice for rickettsial disease. There is currently no proven specific treatment for arboviral diseases. Prevention remains the mainstay for arthropod vector and zoonotic disease control.

Conclusions

Emerging arthropod vector-borne diseases should be considered in the differential diagnosis of uveitis, especially in patient living or with recent travel to endemic countries. Early clinical diagnosis, while laboratory testing is pending, is essential for proper management to prevent systemic and ocular morbidity.

Rickettsial fever leading to upper disphagya: A rare neurovascular conflict between vertebral artery and glossopharyngeal nerve

Rickettsial fevers are a common type of zoonosis with potential neurological involvement, mostly in form of meningoencephalitis. However, there are some rare cases that could compromise cranial nerves function through vascular inflammation. In this paper, we describe a rare case of dysphagia related to glossopharyngeal involvement by juxtaposed vertebral artery vasculitis.

Ocular manifestation of rickettsial disease in South Indian population

Purpose

The aim of this work was to study the ocular manifestations and its management in spotted fever and typhus group of rickettsial disease.

Methods

A retrospective analysis of 50 patients with serologically confirmed Rickettsial disease. In all patients, relevant history, investigations and treatment details were collected and they underwent complete ophthalmic evaluation including measurement of best-corrected visual acuity, anterior segment examination and dilated fundus examination.

Results

Mean age was 12.5 ± 8.99 years. Of the 50 patients, 40 patients were ≤18 years of age and 27 (54%) had ocular involvement. Out of 27 patients, bilateral involvement was seen in 10 patients. Most of the patients had no ocular symptoms. Ocular findings included, Retinal vasculitis 6 (22.22%); macular edema 4 (14.81%); vasculitis with macular edema 1 (3.7%); Retinitis 7 (25.92%); Papilloedema 6 (22.22%); Papilloedema with 6^th cranial nerve palsy 1 (3.7%); Isolated 6^th cranial nerve palsy 1 (3.7%) and optic neuritis 1 (3.7%). Ocular involvement was more common in double antigen group (68%) than spotted fever group (50%) or Scrub typhus group (21%) (P = 0.01). Ocular involvement was seen in 94% of the patients with CNS involvement. Cases with bilateral involvement (P = 0.01), pediatric age group (P = 0.01) and CNS involvement (P = 0.02) had poor visual outcome.

Conclusion

Rickettsioses patients can have ocular manifestations with predominant posterior segment involvement during acute phase of illness. Ocular involvement was more common in the double antigen group. For any patient who presents with fever and rash living in endemic area, ophthalmic evaluation should be part of routine checkup during the acute phase of illness associated with less frequent ocular symptoms.

Rickettsial neuroretinitis: A report of 2 cases

Purpose

The authors present two cases of neuroretinitis caused by Rickettsia rickettsii infection.

Observations

Case 1 is a 24-year-old male who presented with 2 months of vision loss. Case 2 is a 38-year-old female who presented with 4 weeks of eye pain and vision loss. Examination of both patients revealed neuroretinitis characterized by optic disc swelling with macular exudates, and subsequent serological analysis was positive for Rickettsia rickettsii. Both patients responded favorably to treatment with oral doxycycline and prednisone.

Conclusions and importance

Given the potential for neuroretinitis to cause permanent vision loss, the presence of acute vision loss, optic disc edema, and macular exudates should prompt an evaluation for Rickettsial disease in endemic areas, even in the absence of systemic symptoms or known history of a tick bite.

Clinical features, optical coherence tomography findings and treatment outcomes of post-fever retinitis

Objectives:

To study the clinical features, optical coherence tomography (OCT) findings, treatment options and follow-up outcomes of post-fever retinitis (PFR).

Subjects:

A total of 19 eyes of 13 patients, diagnosed with PFR (retinitis following febrile episode) over 2 years were retrospectively studied.

Methods:

Documented history, baseline clinical features and systemic investigations performed for PFR were reviewed. Fundus findings, foveal architecture on swept-source OCT, the treatment options and the follow-up outcomes including best-corrected visual acuity (BCVA) and central foveal thickness (CFT) were reviewed and analyzed.

Results:

Common fundus findings included whitish retinitis lesions (100%), macular star (95%, 18eyes), retinal flame-shaped hemorrhages (63%, 12 eyes), inflammatory retinal vessels (30%, 6 eyes), vitreous hemorrhage (one eye) and OCT findings included neuro-sensory detachment (79%, 15 eyes), intraretinal white dots (89.5%,17 eyes). The baseline median log MAR BCVA and CFT were 1.30 (interquartile range (IQR):0.8–1.8) and 423 microns (IQR:182–555). Overall, nine patients (12 eyes) received a combination of oral doxycycline and oral steroids and four patients (7 eyes) received a combination of oral doxycycline, oral steroid and intravitreal anti-vascular endothelial growth factor (IVA). Significant improvement was evident at 8 weeks in median BCVA (0.50, IQR: 0.3–0.8, p < 0.05) and median CFT (223 micron, IQR: 170–256, p < 0.05) though only 26% (5 eyes) attained BCVA > = 6/12.

Conclusion:

Our study puts forth certain characteristic fundus and OCT features of PFR. A combination of oral doxycycline and oral steroids as a treatment option showed improvement in BCVA and CFT. Additional IVA helps in faster visual recovery in patients presenting with severe macular edema at onset.

Advances and potential new developments in imaging techniques for posterior uveitis. Part 1: noninvasive imaging methods

The aim of this review was to identify the imaging methods at our disposal to optimally manage posterior uveitis at the present time. The focus was put on methods that have become available since the 1990s, some 30 years after fluorescein angiography had revolutionized imaging of posterior uveitis in particular imaging of the retinal vascular structures in the 1960s. We have focussed our review on precise imaging methods that have been standardized and validated and can be used universally thanks to commercially produced and available instruments for the diagnosis and follow-up of posterior uveitis. The first part of this imaging review will deal with noninvasive imaging methods, focusing on fundus autofluorescence and optical coherence tomography as well as recent developments in imaging of the posterior segment.

Post-fever retinitis - Newer concepts

Post-fever retinitis (PFR) is an infectious or para-infectious uveitic entity caused by bacterial or viral agents and seen mainly in tropical countries. Systemic symptoms such as joint pain, skin rash are common during the febrile stage. On the basis of only clinical presentation, it is difficult to pin-point the exact etiology for PFR. Serological investigations, polymerase chain reaction, and knowledge of concurrent epidemics in the community may help to identify the etiological organism. Bacterial causes of PFR such as rickettsia and typhoid are treated with systemic antibiotics, with or without systemic steroid therapy, whereas PFR of viral causes such as chikungunya, dengue, West Nile virus, and Zika virus have no specific treatment and are managed with steroids. Nevertheless, many authors have advocated mere observation and the uveitis resolved with its natural course of the disease. In this article, we have discussed the clinical features, pathogenesis, investigations, and management of PFR.

Ocular manifestations of dermatological diseases part I: infectious and inflammatory disorders

Skin and eyes share a common embryological origin from the embryonic surface ectoderm. Ocular manifestations are one of the most important and common associations of dermatological diseases. Currently, there are few comprehensive reviews of the ocular manifestations of dermatological diseases. We have reviewed more than 40 published articles related to the ocular manifestations of the most important dermatological diseases. The search included Pubmed, Google Scholar, and Cochrane databases from 2014 to 2019. This review was divided into three parts including infections, inflammatory, genetics, connective tissue, autoimmune, neoplasms, and drug-related disorders. We excluded metabolic, endocrine, and nutrition-related dermatological diseases. The relationship of ocular manifestations and dermatological diseases is important to recognize for appropriate management since many dermatological diseases can manifest initially with ocular findings. In this part, we summarized the most common and significant ocular findings in infectious and inflammatory dermatological disorders with appropriate referral recommendations to ophthalmology.

Two cases of uveitis associated with severe transaminitis during a Rickettsia typhi outbreak in Los Angeles County

Purpose

To report the clinical presentation, multimodal imaging, and management of two patients with Rickettsia typhi infection who presented with transaminitis and bilateral uveitis.

Observations

We report two cases of murine typhus-associated uveitis in the setting of a Rickettsia typhi outbreak in Los Angeles County. In case 1, a 29-year-old Hispanic female presented with scotoma of the right eye and bilateral floaters after 2 weeks of persistent fevers, maculopapular rash, and arthralgia. Clinical examination and optical coherence tomography (OCT) revealed vitreous cell and scattered white spots in both eyes at the level of the inner retina, and a cotton wool spot inferiorly in the left eye. Multiple hyperautofluorescent spots were seen on widefield fundus autofluorescence (FAF). Retinal vascular leakage and optic disc hyperfluorescence were visualized on widefield fluorescein angiography (FA). These findings were concerning for a white dot syndrome (WDS). The patient was started on oral prednisone 30 mg daily. Serologic testing during the convalescent phase returned positive for R. typhi infection and she was started on doxycycline. 3 weeks later, she reported complete resolution of scotoma and significant improvement of bilateral floaters.

In the second case, a 42-year-old Hispanic male presented with sudden bilateral increased floaters and blurry vision after 12 days of persistent fever and headache. Clinical examination revealed trace flare with 1+ cell in the anterior chamber, 1+ vitreous cell, and multiple white dots in both eyes at the level of the inner retina. FAF showed scattered hyperautofluorescent spots in both eyes. FA demonstrated late retinal vascular leakage with bilateral hyperfluorescent optic discs. He was started on oral prednisone 40mg, prednisolone acetate 1% drops, and cyclopentolate 1% drops daily. 2 weeks later, serologic titers returned positive for murine typhus and he was started on doxycycline with gradual taper off of steroids. He subsequently had complete resolution of floaters, blurry vision, and the inner retinal white spots.

Conclusions and Importance

Murine typhus-associated uveitis may present with scotoma and increased floaters in the setting of persistent fevers and transaminitis, with pre- or inner retinal white spots seen on fundus examination. Ophthalmologists may aid in prompt diagnosis and initiation of antibiotic therapy, which can shorten the course of the disease and in turn, reduce the risk of severe complications.

Rickettsia conorii retinitis: an emerging infection in the southeast of the Iberian Peninsula

CASE REPORT

A case is presented of a 60-year-old patient with loss of visual acuity in both eyes after fever and skin rash with palmoplantar involvement. After a complete examination and relevant complementary tests, the diagnosis of retinitis was made in the context of Rickettsia conorii infection. The evolution after treatment with doxycycline and prednisone at six weeks with significant anatomical and functional improvement is presented. Rickettsiosis is an emerging zoonosis that can present with ocular involvement. This is usually a multifocal retinitis affecting posterior pole with macular serous detachment and vitritis. Clinical suspicion will require serological confirmation for a definitive diagnosis. Treatment with antibiotics and corticosteroids has been shown to be effective. It should be taken into account in Mediterranean endemic areas, and in in the summer period, where the risk is much higher.

SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN RICKETTSIAL RETINITIS

PURPOSE

To report optical coherence tomography angiography findings in a patient with rickettsial retinitis.

METHODS

A 29-year-old man complaining of acute blurring vision in the right eye associated with Rickettsia conorii infection underwent a comprehensive ocular examination, fluorescein angiography, spectral-domain optical coherence tomography, and swept-source optical coherence tomography angiography.

RESULTS

Funduscopy showed two large areas of retinitis in the inferior macula along the distribution of the inferotemporal artery with associated retinal hemorrhages, retinal edema, and serous retinal detachment. Fluorescein angiography showed early hypofluorescence and late staining of white retinal lesions and associated adjacent retinal vascular leakage and optic disc hyperfluorescence. Optical coherence tomography angiography showed hypointense dark areas in the superficial capillary plexus and larger hypointense areas in the deep capillary plexus, outer retina, and choriocapillaris layer. The patient was treated with doxycycline and prednisone. Six weeks after presentation, retinal changes seen at the acute phase had resolved, leading to mild residual retinal pigment epithelial changes. Fluorescein angiography showed retinal capillary nonperfusion within areas of resolved retinitis. Spectral-domain optical coherence tomography findings included inner retinal atrophy, intraretinal cysts, and disruption of ellipsoid zone and interdigitation zone. Swept-source optical coherence tomography angiography showed well-delineated hypointense greyish areas of retinal capillary nonperfusion in both the superficial and deep capillary plexuses. Visual field testing revealed the presence of a corresponding paracentral defect.

CONCLUSION

Optical coherence tomography angiography may be a valuable noninvasive imaging technique for detecting and analyzing occlusive complications associated with rickettsial retinitis.

Rickettsial infections of the central nervous system

As a result of migrations and globalization, people may face a possible increase in the incidence of central nervous system rickettsial infections (CNS R). These diseases, caused by Rickettsia species and transmitted to humans by arthropod bites, are putatively lethal. However, the diagnosis of CNS R is challenging and often delayed due to their nonspecific clinical presentation and the strict intracellular nature of rickettsiae. Furthermore, transfer of rickettsiae to the brain parenchyma is not yet understood. The aim of this review is to analyze and summarize the features and correlated findings of CNS R in order to focus attention on these intriguing but frequently neglected illnesses. We also incorporated data on CNS infections caused by Rickettsia-related microorganisms.

Optical coherence tomography angiography features of retinitis post-rickettsial fever

The intraocular manifestations of rickettisial retinitis include retinal vasculitis, maculopathy, optic neuritis, and neurosensory detachment. Extensive leakage of dye on the fundus fluorescein angiography may obscure visualization in eyes with retinitis. We report the vascular changes in eyes with rickettsial retinitis and its response to treatment using optical coherence tomography angiography. The microvascular abnormalities we noted were, capillary drop out areas corresponding to retinitis patches, vascular loops, and pruning of vessels. The choriocapillary slabs showed signal void areas. Post-treatment there was vascular remodeling with decrease in non-perfused area, appearance of new vascular lateral branching, and appearance of collaterals.

Ocular manifestations of Rickettsia conorii in South India

Purpose:

Among the major groups of rickettsiosis, the commonly reported diseases in India are: (a) Typhus group induced—scrub typhus, murine flea-borne typhus; (b) Spotted fever group induced—Indian tick typhus; and (c) Q fever. Though many scrub typhus outbreaks have been reported from India, only one outbreak of spotted fever—serologically proven Indian tick typhus (Rickettsia conorii)—has been reported. We report for the first time ocular manifestations of serologically proven R. conorii infection in a cluster of patients.

Methods:

In this retrospective study, case records patients with serologically proven Indian tick typhus (Rickettsia conorii) were reviewed for clinical manifestations and treatment outcomes.

Results:

In the months of February to April 2016, a cluster of 12 patients (23 eyes) visited us with defective vision. Examination showed multifocal retinitis; mostly bilateral; patients had a history of fever approximately 4 weeks prior to onset of symptoms. After excluding other causes of multifocal retinitis, a diagnosis of rickettsial retinitis was made after Weil–Felix test (WFT) was significantly positive, and enzyme-linked immunosorbent assay was positive for R. conorii. Course of the disease, visual outcome, and investigations are discussed. Doxycycline along with oral corticosteroids was effective in treating the condition.

Conclusion:

Systematic fundus examination should be part of the routine evaluation of any patient who presents with fever and/or skin rash living in or returning from a specific endemic area. Clinical clues to diagnosing ocular rickettsiosis could be multifocal retinitis predominantly involving the posterior pole and macular involvement in the form of serous macular detachment or macular hard exudates. A positive WFT still serves as a useful and cheap diagnostic tool for laboratory diagnosis of rickettsial disease. Doxycycline along with oral corticosteroids was effective in treating the condition.

An imaging-based treatment algorithm for posterior focal retinitis

Background:

In this paper, our aim was to describe an imaging-based empirical approach for categorizing and initiating treatment of immunocompetent patients with posterior focal retinitis, prior to the availability of results of expensive laboratory investigations.

Materials and methods:

The hospital records of 13 patients with posterior focal retinitis were reviewed.

Results:

Of the 13 patients, 9 were women and 4 were men. The mean age was 24 ± 8 years. Based on similarities in clinical presentation and imaging, we categorized our cases into three groups with different first-line therapeutic strategies. In the first group, patients had presumed toxoplasmosis (treated with oral cotrimoxazole); in the second group, patients had presumed viral (herpetic) etiology (treated with oral valacyclovir); and in the third group, patients had presumed nonherpetic, nontoxoplasma retinitis (treated with oral doxycycline). Positive serology results included Rickettsia (two patients), Borrelia (one patient), Toxoplasma (two patients), and herpes simplex virus (one patient).

Conclusion:

An empirical approach for early initiation of therapy in retinitis cases based on imaging features is described.

Ocular manifestations of rickettsia in children: common but frequently overlooked

We review two cases of ocular manifestations of Rickettsia conorii infection in children. A girl who presented unilateral visual loss with focal retinitis and macular oedema and a boy with unilateral central scotoma and bilateral anterior uveitis. Progressive functional and anatomic recovery was observed after oral antibiotics and steroids were initiated.

Final Diagnosis in Patients Referred with a Diagnosis of Neuroretinitis

The purpose of this study was to determine final diagnosis of patients referred with a diagnosis of neuroretinitis. A retrospective study of 40 patients with optic disc oedema with macular star (ODOMS) referred with a diagnosis of neuroretinitis was conducted. The final diagnosis was neuroretinitis in 26 patients (65%), with most of these patients (96.1%) having unilateral involvement. Main underlying aetiologies included cat scratch disease (30.8%), rickettsiosis (19.2%), and idiopathic neuroretinitis (23.1%). The remaining 14 patients (35%) had ODOMS that had been mistaken for neuroretinitis. Of these patients, 42.8% were found to have a previously unknown malignant systemic hypertension in association with bilateral ODOMS. Neuroretinitis, usually unilateral, should be differentiated from other causes of unilateral or most often bilateral ODOMS that may masquerade as neuroretinitis, mainly malignant systemic hypertension. This is essential to avoid inappropriate work-up and management and subsequent potential visual or systemic morbidity.

Rickettsial retinitis-an Indian perspective

BACKGROUND

Though rickettsiosis is common in India, there is paucity of rickettsial retinitis (RR) reports from India. Moreover, rickettsial sub-types and their association with retinitis have not been studied. We are reporting a case series of presumed RR with their course of the disease, visual outcome, and association with rickettsial sub-type based on Weil-Felix test.

FINDINGS

This is a retrospective study of 19 eyes of 10 patients presented to a single institution. Cases diagnosed with presumed RR were identified from our database from March 2006 to October 2014 and studied retrospectively for patient's demography, clinical presentation, and treatment. Patients with history of fever, retinitis, and a positive Weil-Felix test and a negative chikungunya and dengue serology were diagnosed as presumed rickettsial uveitis. One patient was diagnosed to have epidemic typhus, and four were diagnosed to have Indian tick typhus. Nine patients had bilateral presentation. One patient had history of dog tick bite, and four patients had skin rashes. All the patients presented between 2 and 4 weeks after a fever.

CONCLUSIONS

Retinitis on posterior pole with recent history of fever with or without skin rash and a positive Weil-Felix test may suggest a rickettsial etiology. Its ocular manifestation could be an immune response to recent systemic rickettsial infection. Indian tick typhus and epidemic typhus could be the common sub-types seen in our population. Although it has aggressive presentation, it has a good visual prognosis.

Infectious optic neuropathies: a clinical update

Different forms of optic neuropathy causing visual impairment of varying severity have been reported in association with a wide variety of infectious agents. Proper clinical diagnosis of any of these infectious conditions is based on epidemiological data, history, systemic symptoms and signs, and the pattern of ocular findings. Diagnosis is confirmed by serologic testing and polymerase chain reaction in selected cases. Treatment of infectious optic neuropathies involves the use of specific anti-infectious drugs and corticosteroids to suppress the associated inflammatory reaction. The visual prognosis is generally good, but persistent severe vision loss with optic atrophy can occur. This review presents optic neuropathies caused by specific viral, bacterial, parasitic, and fungal diseases.