Impact of a Severe Rocky Mountain Spotted Fever Case on Treatment Practices at an Academic Institution Within a Nonendemic Area.

INTRODUCTION: Rocky Mountain spotted fever (RMSF) is a bacterial disease associated with morbidity and mortality when untreated. The primary study objectives are to describe clinician diagnostic and treatment practices in a nonendemic area after the occurrence of an unrecognized severe pediatric presumed RMSF case (index case). We hypothesized that inpatient diagnostic testing frequency and initiation of empiric treatment will increase after the index case. METHODS: We performed a retrospective chart review of patients aged less than 18 y evaluated for RMSF at Penn State Hershey Children's Hospital between 2010 and 2019. We divided the study population into 2 groups (preindex and postindex) and evaluated patient characteristics, RMSF testing completion, and timing of doxycycline administration. RESULTS: Fifty-four patients (14 [26%] preindex and 40 [74%] postindex) were included. Age (median [25th percentile, 75th percentile]) decreased from 14.5 y (8.6, 16) preindex to 8.3 y (3.6, 14) postindex. Twelve (86%) preindex and 31 (78%) postindex patients received empiric doxycycline (P=0.70). Four years after the index case, a decrease in empiric and urgent initiation of doxycycline administration was noted. One case of severe RMSF was diagnosed 4 y after the index case. CONCLUSIONS: Our study found that inpatient RMSF testing increased after the index case, but not all patients received empiric treatment. This may represent an underappreciation of RMSF severity even after a recent devastating case. We suggest that when severe rare but possibly reversible diseases, such as RMSF occur, all clinicians are educated on the diagnostic and treatment approach to reduce the morbidity and mortality risk.

Clinical characteristics of Rocky Mountain spotted fever in the United States: A literature review.

BACKGROUND AND OBJECTIVES: Rocky Mountain spotted fever (RMSF) is a rapidly progressive and potentially fatal tickborne disease caused by Rickettsia rickettsii. Despite current recommendations and information on the severity of RMSF, studies show that delayed recognition and treatment continues to occur. METHODS: A literature search was performed on cases published in English between 1990-2017. The frequencies for demographic, clinical, and treatment variables was calculated. RESULTS: A total of 340 cases from 34 articles were included. Data on rash were available for 322 patients, and 261 (80%) noted rash. Mortality was 4% (2) in those who received doxycycline within the first five days of illness, and 35% (18) when treatment was delayed beyond Day five. Twenty-four (16%) reported chronic sequelae, including speech impairment (7, 5%) and ataxia (5, 3%). INTERPRETATION AND CONCLUSION: These data highlight the importance of early treatment, and add to our understanding of long-term sequelae. Early recognition by providers will facilitate appropriate treatment and reduction in morbidity and mortality.

Rocky mountain spotted fever characterization and comparison to similar illnesses in a highly endemic area-Arizona, 2002-2011.

BACKGROUND: Rocky Mountain spotted fever (RMSF) has emerged as a significant cause of morbidity and mortality since 2002 on tribal lands in Arizona. The explosive nature of this outbreak and the recognition of an unexpected tick vector, Rhipicephalus sanguineus, prompted an investigation to characterize RMSF in this unique setting and compare RMSF cases to similar illnesses. METHODS: We compared medical records of 205 patients with RMSF and 175 with non-RMSF illnesses that prompted RMSF testing during 2002-2011 from 2 Indian reservations in Arizona. RESULTS: RMSF cases in Arizona occurred year-round and peaked later (July-September) than RMSF cases reported from other US regions. Cases were younger (median age, 11 years) and reported fever and rash less frequently, compared to cases from other US regions. Fever was present in 81% of cases but not significantly different from that in patients with non-RMSF illnesses. Classic laboratory abnormalities such as low sodium and platelet counts had small and subtle differences between cases and patients with non-RMSF illnesses. Imaging studies reflected the variability and complexity of the illness but proved unhelpful in clarifying the early diagnosis. CONCLUSIONS: RMSF epidemiology in this region appears different than RMSF elsewhere in the United States. No specific pattern of signs, symptoms, or laboratory findings occurred with enough frequency to consistently differentiate RMSF from other illnesses. Due to the nonspecific and variable nature of RMSF presentations, clinicians in this region should aggressively treat febrile illnesses and sepsis with doxycycline for suspected RMSF.

No visible dental staining in children treated with doxycycline for suspected Rocky Mountain Spotted Fever.

OBJECTIVE: To evaluate whether cosmetically relevant dental effects occurred among children who had received doxycycline for treatment of suspected Rocky Mountain spotted fever (RMSF). STUDY DESIGN: Children who lived on an American Indian reservation with high incidence of RMSF were classified as exposed or unexposed to doxycycline, based on medical and pharmacy record abstraction. Licensed, trained dentists examined each child's teeth and evaluated visible staining patterns and enamel hypoplasia. Objective tooth color was evaluated with a spectrophotometer. RESULTS: Fifty-eight children who received an average of 1.8 courses of doxycycline before 8 years of age and who now had exposed permanent teeth erupted were compared with 213 children who had never received doxycycline. No tetracycline-like staining was observed in any of the exposed children's teeth (0/58, 95% CI 0%-5%), and no significant difference in tooth shade (P=.20) or hypoplasia (P=1.0) was found between the 2 groups. CONCLUSIONS: This study failed to demonstrate dental staining, enamel hypoplasia, or tooth color differences among children who received short-term courses of doxycycline at <8 years of age. Healthcare provider confidence in use of doxycycline for suspected RMSF in children may be improved by modifying the drug's label.

Self-reported treatment practices by healthcare providers could lead to death from Rocky Mountain spotted fever.

Among 2012 Docstyle survey respondents, 80% identified doxycycline as the appropriate treatment for Rocky Mountain spotted fever in patients ≥ 8 years old, but only 35% correctly chose doxycycline in patients <8 years old. These findings raise concerns about the higher pediatric case-fatality rate of Rocky Mountain spotted fever observed nationally. Targeted education efforts are needed.

Acute infectious purpura fulminans due to probable spotted fever.

Purpura fulminans (PF) is associated with several infections, most notably with meningococcus, staphylococcus, and streptococcus infections. However, there are few reports of association of this entity with spotted fever from India. We report the case of a 55-year-old man who presented with fever, headache, and myalgia. On the seventh day of fever he developed nonblanching purple hemorrhagic purpura on the trunk and most prominently on the extremities consistent with purpura fulminans. Immunofluorescent assay confirmed the diagnosis of spotted fever. PF though common with rocky mountain spotted fever (RMSF) is rarely seen in association with Indian tick typhus, the usual cause of spotted fever in India.

Why sulfonamides are contraindicated in Rocky Mountain spotted fever.

Sulfonamide antibiotics are not effective for the treatment of Rocky Mountain spotted fever (RMSF). Patients suspected of having RMSF based on history and physical exam should be treated with doxycycline and not a sulfonamide to avoid increased morbidity and mortality.

Fever and Rash.

Infectious causes of fever and rash pose a diagnostic challenge for the emergency provider. It is often difficult to discern rashes associated with rapidly progressive and life-threatening infections from benign exanthems, which comprise the majority of rashes seen in the emergency department. Physicians must also consider serious noninfectious causes of fever and rash. A correct diagnosis depends on an exhaustive history and head-to-toe skin examination as most emergent causes of fever and rash remain clinical diagnoses. A provisional diagnosis and immediate treatment with antimicrobials and supportive care are usually required prior to the return of confirmatory laboratory testing.

Case Report: Fatal Rickettsiosis in Pregnancy.

Rocky Mountain spotted fever (RMSF) is a tick-borne infection caused by Rickettsia rickettsii. We present a series of two cases of pregnant patients who showed up at the emergency room of a hospital in Nuevo León, Mexico. Both patients lived in environments where R. rickettsii is endemic and they presented with several days of symptoms, including fever. Both patients developed a rash and had stillbirths during their hospital stay. Treatment with doxycycline was delayed, with fatal results in both patients. Diagnosis of RMSF was confirmed via polymerase chain reaction assay postmortem. The need to link epidemiological clues with clinical data is critical in the diagnosis and early treatment of RMSF to prevent maternal deaths.

Does Paging Clinicians about Tick-Borne Disease Serological Results Impact Clinical Care? A Retrospective Analysis of 70 Cases in North Carolina.

Delayed treatment of Rocky Mountain spotted fever is associated with increased morbidity and mortality. Because the diagnosis cannot be established from a single serological test, guidelines recommend empirical antibiotic initiation in suspect patients. We evaluated a policy used by UNC Health of paging clinicians when acute testing for Rickettsia returned with a titer ≥1:256. Our objective was to assess the potential effect of paging on routine treatment practices. Notably, we found that a high proportion of cases (N = 28, 40%) were not prescribed antibiotics until the results were available. The vast majority of these cases did not have evidence of compatible symptoms or disease progression. These findings suggest that paging may have prompted unnecessary treatment. Overall, the policy, which has now been discontinued, appears to have had limited benefit. Efforts are urgently needed to improve adherence to testing and treatment guidelines.

Rocky Mountain Spotted Fever in a patient treated with anti-TNF-alpha inhibitors.

Rocky Mountain Spotted Fever (RMSF) is a tick-bourne illness, which can be fatal if unrecognized. We discuss the case of a patient treated with an anti-TNF-alpha inhibitor for rheumatoid arthritis who later developed a generalized erythematous macular eruption accompanied by fever. The clinical findings were suggestive of RMSF, which was later confirmed with serology. Prompt treatment with doxyclycine is recommended for all patients with clinical suspicion of RMSF.

Rocky Mountain spotted fever: 'starry sky' appearance with diffusion-weighted imaging in a child.

We present a case of Rocky Mountain spotted fever encephalitis in a child imaged utilizing diffusion-weighted MRI. Although the imaging and clinical manifestations of this entity have been previously described, a review of the literature did not reveal any such cases reported in children utilizing diffusion-weighted imaging. The imaging findings and clinical history are presented as well as a brief review of this disease.

An Unsuspected Case of Rocky Mountain Spotted Fever: A Lesson to Keep a Broad Differential.

Rocky Mountain spotted fever (RMSF), a tick-borne illness, can cause serious illness or death even in a healthy individual. Unfortunately, this illness can be difficult to diagnose as symptoms are nonspecific and oftentimes mimic benign viral illnesses. Delayed diagnosis can be detrimental as the timing of antibiotic administration is critical to prevent associated morbidity and mortality. A careful travel and social history can sometimes provide clues to make the diagnosis. Being aware of lesser-known objective findings such as hyponatremia, neurologic derangements, transaminitis, and thrombocytopenia may help raise suspicion for the disease. This is a case of a 72-year-old woman who presented with nonspecific symptoms and hyponatremia without known tick exposure. She was eventually diagnosed with RMSF. The timing of her presentation corresponded with a surge in COVID-19 infections throughout her area of residence, which further complicated her presentation and contributed to a delayed diagnosis.

Knowledge, Attitudes, and Practices on Rocky Mountain Spotted Fever among Physicians in a Highly Endemic Region-Mexicali, Mexico.

Rocky Mountain spotted fever (RMSF) is a potentially fatal tickborne disease caused by the bacterium, Rickettsia rickettsii and transmitted primarily by the brown dog tick (Rhipicephalus sanguineus) in the southwestern United States and Mexico. RMSF can be rapidly fatal if not treated early with doxycycline, making healthcare worker awareness and education critical to reduce morbidity and mortality. During 2008-2019, Mexicali experienced a RMSF epidemic with 779 confirmed cases, and an 11-year case-fatality rate of 18% (N = 140). A cross-sectional study was conducted with 290 physicians and physicians-in-training across 12 medical facilities in Mexicali. They were asked to complete a 23-item questionnaire to assess knowledge, attitudes, and practices for clinical, epidemiologic, and preventive aspects of RMSF. Half of participants were female, the largest age group was aged 25 to 44 (47%), and median time in practice was 6 years (interquartile rate: 1-21.5). Less than half (48%) surveyed were confident where diagnostic testing could be performed, and two-thirds did not regularly order serology (67%) or molecular diagnostic (66%) tests for RMSF when a patient presented with fever. Sixty-four percent knew doxycycline as first-line treatment of children < 8 years with suspected RMSF. When comparing healthcare workers with < 6 years of experience to those with ≥ 6 years, more experience was associated with greater confidence in where to have diagnostic testing performed (prevalence odds ratio [prevalence odds ratios [pOR]] = 2.3; P = 0.004), and frequency of ordering laboratory tests (serology, pOR = 3.3; P = 0.002; polymerase chain reaction, pOR = 3.9; P = 0.001). Continued education, including information on diagnostic testing is key to reducing morbidity and mortality from RMSF.

Emerging Spotted Fever Rickettsioses in the United States.

Spotted fever rickettsioses are important causes of emerging infectious disease in the United States and elsewhere. Rocky Mountain Spotted Fever, caused by R. rickettsii causes a febrile, acute illness in dogs. Because it circulates in peripheral blood in low copy number and because of the acute nature of the disease, dogs may test PCR and seronegative at the time of presentation. Therefore, therapy with doxycycline must be initiated and continued based on the clinician's index of suspicion. Combining PCR with serologic testing, repeat testing of the same pre-antimicrobial blood sample, and testing convalescent samples for seroconversion facilitates diagnosis. The prognosis can be excellent if appropriate antimicrobial therapy is begun in a timely fashion. It is well established that dogs are sentinels for infection in people in households and communities. Whether R. rickettsii causes illness in cats is not well established. The role of other spotted fever group rickettsia in causing illness in dogs and cats is being elucidated. Veterinarians should keep in mind that novel and well characterized species of SFG Rickettsia are important causes of emerging infectious disease. Veterinarians can play an important role in detecting, defining, and preventing illness in their canine patients and their human companions.

Rickettsia rickettsii transmission by a lone star tick, North Carolina.

Only indirect or circumstantial evidence has been published to support transmission of Rickettsia rickettsii by Amblyomma americanum (lone star) ticks in North America. This study provides molecular evidence that A. americanum ticks can function, although most likely infrequently, as vectors of Rocky Mountain spotted fever for humans.

Tick-borne illnesses: a CME update.

North American tick-borne illnesses are a group of important emerging diseases whose incidence has been increasing for the past decade. Emergency physicians may be the first contact for patients with symptoms of tick-borne illness, thus it is important that these diseases remain on a physicians' differential diagnosis when presented with an appropriate clinical presentation. This CME activity provides an overview of the most common tick-borne illnesses in North America and will help physicians evaluate their clinical presentation, order appropriate diagnostic tests, develop pediatric treatment recommendations, and prepare to include tick-borne illnesses in the differential diagnosis of pediatric patients presenting with multisystem disease.

Knowledge, Attitudes, and Practices Related to Rocky Mountain Spotted Fever in Hermosillo, México.

Rocky Mountain spotted fever (RMSF) is a serious disease in northwest Mexico, particularly in low-income communities. This study aimed to evaluate RMSF-related knowledge, attitudes, and practices in an endemic urban area with a high burden of the disease. A cross-sectional study design using a non-probabilistic household survey was conducted with 400 residents in Hermosillo, Mexico. Primary themes assessed included dog and tick-related exposure, RMSF knowledge, healthcare-seeking behavior, sociodemographic data, and household information. The majority (59%) of those surveyed had heard about RMSF, although only 36% of RMSF-aware respondents knew any RMSF symptoms. Among RMSF-aware respondents, 26% did not know or were unsure of prevention strategies. Individuals in the low socioeconomic status (SES) stratum were less likely to have heard about RMSF (odds ratio [OR]: 0.39; 95% CI: 0.25-0.59), use dog collars or any other product to avoid ticks (OR: 0.40; 95% CI: 0.17-0.99), or check their dogs for ticks (OR: 0.25; 95% CI: 0.09-0.74). The likelihood of observing high numbers of free-roaming dogs in their neighborhood was four times higher in the low SES stratum (OR: 4.19; 95% CI: 2.10-8.38) than in the high SES stratum. These findings emphasize the need for an integrative community approach to improve early recognition of symptoms and knowledge of prevention strategies, particularly in low SES neighborhoods.