Thrombocytopenia Associated with Elemental Mercury Poisoning in Two Siblings - Connecticut, July 2022.

Two siblings aged 5 and 15 years from Connecticut were hospitalized with petechial rash, oral mucositis, and severe thrombocytopenia approximately 10 days after they played with a jar of elemental mercury they found in their home. Before the mercury exposure was disclosed, the siblings were treated with platelet transfusions, intravenous immune globulin (IVIG) for possible immune thrombocytopenic purpura, and antibiotics for possible infectious causes. When their conditions did not improve after 6 days, poison control facilitated further questioning about toxic exposures including mercury, testing for mercury, and chelation with dimercaptosuccinic acid. The older sibling soon recovered, but the younger child required a prolonged hospitalization for severe thrombocytopenia, ultimately receiving repeated doses of IVIG, steroids, and romiplostim, a thrombopoietin receptor agonist. Close collaboration among multiple agencies was required to identify the extent of mercury contamination, evaluate and treat the other family members, and decontaminate the home. These cases demonstrate the importance of ongoing public health outreach to promote early detection of elemental mercury toxicity, and the need to evaluate for environmental exposures when multiple close contacts experience similar signs and symptoms.

Lack of Convincing Evidence That Borrelia burgdorferi Infection Causes Either Alzheimer Disease or Lewy Body Dementia.

The role that microorganisms might have in the development of Alzheimer disease is a topic of considerable interest. In this article, we discuss whether there is credible evidence that Lyme disease is a cause of Alzheimer disease and critically review a recent publication that claimed that Borrelia burgdorferi sensu stricto infection, the primary cause of Lyme disease in the United States, may cause Lewy body dementia. We conclude that no convincing evidence exists that Lyme disease is a cause of either Alzheimer disease or Lewy body dementia.

"COVID Toes" in Three Siblings.

Dermatologists reported an outbreak of pernio (red to purple swollen painful toes) during the COVID-19 pandemic. Most subjects lacked positive CoV-19 polymerase chain reaction (PCR) or antibodies or a preceding illness. The dermatologists termed the illness "COVID toes." Pernio usually affects adults versus "COVID toes" usually children. Pernio is preceded by a clear history of exposure to wet and cold. Patients with "COVID toes" lack this history. Also, it is not unusual for multiple family members to have "COVID toes." Our case report describes "COVID toes" in an 18-year-old with no preceding illness, a negative SARS-CoV-19 PCR, and an initially negative SARS-CoV-19 antibody, and also his 2 siblings also developed "COVID toes." In our index case, repeat SARS-CoV-19 antibodies were positive. Seroconversion has rarely been reported in patients with "COVID toes." Why most "COVID toes" patients lack a clinical history of COVID-19 and are SARS-CoV-19 PCR and antibody negative is a mystery.

Powassan Virus Encephalitis Following Brief Attachment of Connecticut Deer Ticks.

BACKGROUND: Powassan virus (POWV) is a tick-transmitted pathogen that may cause severe encephalitis; experimentally, it can be transmitted within just 15 minutes following a tick bite. The deer tick virus subtype of POWV (DTV) is transmitted by the deer tick and is the likely cause of the increase in the number of POWV cases reported in the United States. However, DTV has only been definitively documented in 6 patients by molecular analysis of the virus. METHODS: Two patients from Connecticut with encephalitis, who had a recent deer tick bite, were evaluated by the relevant serologic tests to determine if they had been infected with POWV. Evaluation also included molecular testing of an adult deer tick that had been removed from one of the patients. RESULTS: We documented neuroinvasive POWV infection in 2 children from Connecticut. Based on the results of testing the tick removed from case 2, this patient was infected by DTV, representing the 7th reported case and the first documented case of DTV infection in a child. Of note, the duration of the tick bites in both cases was very short. CONCLUSIONS: We provide the first clinical and epidemiologic evidence that POWV/DTV can be rapidly transmitted to a human host, that is, within hours of tick attachment, which is distinctive when compared to other deer tick-transmitted infections such as Lyme disease.

Common genetic susceptibility loci link PFAPA syndrome, Behçet's disease, and recurrent aphthous stomatitis.

Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome is the most common periodic fever syndrome in children. The disease appears to cluster in families, but the pathogenesis is unknown. We queried two European-American cohorts and one Turkish cohort (total n = 231) of individuals with PFAPA for common variants previously associated with two other oropharyngeal ulcerative disorders, Behçet's disease and recurrent aphthous stomatitis. In a metaanalysis, we found that a variant upstream of IL12A (rs17753641) is strongly associated with PFAPA (OR 2.13, P = 6 × 10-9). We demonstrated that monocytes from individuals who are heterozygous or homozygous for this risk allele produce significantly higher levels of IL-12p70 upon IFN-γ and LPS stimulation than those from individuals without the risk allele. We also found that variants near STAT4, IL10, and CCR1-CCR3 were significant susceptibility loci for PFAPA, suggesting that the pathogenesis of PFAPA involves abnormal antigen-presenting cell function and T cell activity and polarization, thereby implicating both innate and adaptive immune responses at the oropharyngeal mucosa. Our results illustrate genetic similarities among recurrent aphthous stomatitis, PFAPA, and Behçet's disease, placing these disorders on a common spectrum, with recurrent aphthous stomatitis on the mild end, Behçet's disease on the severe end, and PFAPA intermediate. We propose naming these disorders Behçet's spectrum disorders to highlight their relationship. HLA alleles may be factors that influence phenotypes along this spectrum as we found new class I and II HLA associations for PFAPA distinct from Behçet's disease and recurrent aphthous stomatitis.

Anaplasmosis in pediatric patients: Case report and review.

Human granulocytic anaplasmosis (HGA) is a tick-borne infection, characterized as an acute and sometimes severe febrile illness which may be associated with leukopenia and thrombocytopenia. Most case reports of HGA have been in adults, with only 8 case reports of HGA in children. We add a ninth case of HGA, which occurred in a 5-year-old. The paucity of pediatric HGA case reports maybe because publication bias, or HGA in children is a mild illness and children with HGA are less likely than adults to seek medical care, or the diagnosis of HGA requires a blood draw and adults (versus children) are more likely to get diagnostic testing. The 9 case reports in children suggest that pediatric HGA is usually a mild infection and that doxycycline and rifampin are effective therapies. Like adults, children with HGA frequently present with fever, headache, and malaise; however, children are more likely than adults to have abdominal pain as a prominent complaint.

Kikuchi disease in Connecticut.

Kikuchi disease is a self-limited disorder of unknown etiology characterized by focal painful lymphadenitis, fever, and weight loss that can be mistaken for malignancy. Diagnosis is established by node biopsy. Kikuchi disease is endemic in Asia; 10 cases have been reported in the US to date. We report 3 cases and review other US cases.

Atypical hand, foot, and mouth disease: a vesiculobullous eruption caused by Coxsackie virus A6.

A previously well infant aged 9 months presented with an acute, self-limiting illness characterised by high fever and a papular eruption that started on the face. Although fever subsided within 3 days, the rash worsened and extended over the whole body, with some papules evolving into vesiculobullous lesions. The infant had been exposed to children with a similar illness 1 week before onset. PCR of vesicular swabs and stool samples taken on day 6 of illness showed Coxsackie virus A6. The illness resolved within 10 days of onset, although onychomadesis was seen on both big toes at follow-up 5 weeks later. Our case exemplifies the severe, atypical cases of hand, foot, and mouth disease that have been reported worldwide since 2008, and in the USA since the 2011. Atypical hand, foot, and mouth disease is caused by a new lineage of Coxsackie virus A6 and is characterised by high fever and vesiculobullous eruptions on the calves and backs of the hands. Infants with eczema might be predisposed to severe disease.

Fever in returning travelers: a case-based approach.

Overall, 3% to 19% of travelers to the developing world will return to the United States with fever or will develop fever within weeks of their return. When evaluating the returning traveler with fever, it is important to know which pretravel immunizations the patient received; which medications he or she took during travel; the likely pathogen exposures during travel; and the incubation interval between travel and onset of fever. A physical examination that includes a search for focal findings may narrow the list of possible infections. Fever compatible with a common illness that occurs in the United States (e.g., mononucleosis) should always be considered. If the patient has fever without a focus and a tropical infection is suspected, malaria, dengue fever, and typhoid fever are common causes. These infections may appear clinically similar, with symptoms of fever, headache, muscle pain, joint pain, and malaise, and decreased white blood cell and platelet counts. Malaria can usually be diagnosed with a thin blood smear. Dengue fever is a clinical diagnosis. Serologic testing for dengue virus immunoglobulin M and G and virus detection tests can be performed to confirm the diagnosis, but are not immediately available. Typhoid fever can usually be diagnosed with a blood, urine, or stool culture.