Diagnostic Challenges Encountered When Predicting Patterns of Adult Kawasaki Disease; A Case Report.


 The study of medicine has always awed researchers and allowed for quality scientific discoveries. According to several studies, Kawasaki Disease (KD) typically presents in both adults and children with signs and symptoms of; conjunctivitis, fever (for ≥ five days), pharyngitis as well as skin erythema that advances to desquamatory rash that does not spare the palms and soles in many cases. However, marginally minimal amount of studies has investigated symptoms particularly in adults. The purpose is to report diagnostic challenges that happened our way as we tried diagnosing a rare adult case of Kawasaki Disease in an 18-year-old male with no significant past medical history or physical features to suggest KD. The aim of reporting this case was to highlight the difficulty in diagnosing KD but stressing the importance of managing inflammatory symptoms first especially in young adults with ≥ 5 days of high fevers.


Introduction
Kawasaki disease [KD] is an acute necrotizing vasculitis of medium-and small-sized vessels that has predilection for mucocutaneous lymph nodes and coronary arteries. KD occurs mainly in Korean and Japanese infants and children aged 6 months to 5 years. Approximately 15-20% of all untreated patients develop coronary aneurysms and 2-3% die of coronary vasculitis. [1] Complications are usually preventable when the right management is initiated early in the course of disease [2]. The challenges faced during diagnosis of KD is that the diagnostic criteria are non-speci c. Therefore, clinical features may be present in other infectious and autoimmune pathologies. Also, as the etiology remains unknown, there is no speci c diagnostic test to con rm disease. This presents a diagnostic and therapeutic challenge for the treating physician [3]. With about a little over 100 cases described worldwide, the patterns of disease manifestations and complications continue to pose as a conundrum [4].
This 18-year-old male presented with diagnostic challenges which included; fever, rash, throat pain and myalgia. The diagnostic criteria included fever for >/= 5 days, in addition to any 4 of the 5 following symptoms: 1) non-exudative conjunctival injection 2) erythema of hands and feet and periungual desquamation 3) Oral-mucosal changes like; strawberry tongue, 4) polymorphic rash, desquamation and 5) cervical lymphadenopathy. It did not occur in order as some of the symptoms did not show at all like the strawberry tongue [3].
There is no speci c diagnostic test therefore presenting as a formidable challenge to the treating physician and the diagnosis is often one of exclusion. No. of cases reported per 100,000 children under  (135) is similar to that found in Japan. Therefore, though it is still considered a rare disease in the US, it is the most common cause of acquired heart disease in children in the US [5].

Case Presentation
An 18-year-old young man presented to the hospital in early January of 2019 with thrombocytosis and high fever (up to 40°C) unresponsive to anti-in ammatory drugs for the rst two days but with a good response to aspirin after day four. The high fever continued through day six of admission along with other symptoms like persistent headache, malaise, arthralgia and signs of cervical adenopathy. Upon further investigation, lab results also showed in ammation of the liver (hepatitis) with high liver function tests. It was not until day 10 before the desquamatory rash, reddening of eye and throat pain.
This young man did not travel recently either within the country or abroad and he denies intravenous drug use or having new sexual partners or body tattoos as well as no animal exposure. After day ten, he remembered he took some Amoxicillin pills when he was feverish and had itchy skin. On general examination, he was morbidly obese, appeared anxious but was fully oriented to time, place and person. Lab test later revealed a neutrophilic leukocytosis, WBC count was 14,200 cells/ cumm. There was also a mild hepatitis and markers of in ammation (ESR and CRP) were elevated. Leukocytosis and hepatitis were a possibility in IMN, TSS and Kawasaki, however neutrophilic predominance favored Kawasaki and TSS. Patient was re-evaluated at the hospital three days later. By now, he complained of multiple spikes of fever on a daily basis. There was diffuse erythema of tongue and oral mucosa. There was also mild desquamation of rash over face and periungual desquamation which is fairly speci c for Kawasaki.
Our adult 18-year-old patient had persistent headache that subsided only after the administration of IVIG and ASA. Given the patient's age group, history of throat pain and generalized rash worsened with intake of amoxicillin, Infectious Mononucleosis (IMN) was high on our differential. Other differentials considered were; generalized allergic or contact dermatitis reaction and complications of group A streptococcus (GAS) pharyngitis such as Toxic Shock Syndrome, Acute rheumatic fever and Scarlet fever. Appropriate labs done ruled these other conditions out.
While at the hospital, labs were repeated which showed persistence of neutrophil leukocytosis. Ejection Fraction was 65%, there was mild left ventricular hypertrophy (LVH) and tricuspid regurgitation, however, there were no coronary artery aneurysms. Patient was immediately started on an IVIG infusion, high dose aspirin, diphenhydramine and acetaminophen. Patient started to feel much better after the rst infusion. Periungual desquamation soon progressed to a generalized desquamation of both hands and feet. CMV, EBV and Parvovirus B19 IgG antibody was positive, however IgM was negative. In addition, EBV early Ag and nuclear Ag were also positive. This ruled out Infectious mononucleosis and Parvovirus as causes.
ASO and Anti-DNase B were elevated which proved prior strep infection and was likely the cause for this presentation. Blood cultures showed a preliminary result and later reviewed Gram-positive rods; Corynebacterium manumission, Corynebacterium amycolatum and Diphtheriods which was considered to be a contaminant from the IV line.
Despite 50 years of research in this condition, there is only a small body of literature describing new onset Kawasaki disease in adults. Coronary artery aneurysm occurs in 15-25% of untreated children up to 5 % of treated ones.
[6] Short term sequelae of coronary aneurysms; death due to coronary vasculitis have been identi ed and long-term consequences of endothelial dysfunction, coronary artery disease and myocardial infarction have been described in survivors [7][8]. There is also a drastic reduction in complications if identi ed and treated within 10 days of onset of symptoms [9] [10].
After discharge, desquamation progressed to involve both nails in hands and feet as well.
Onychomadesis has been described in Kawasaki only twice before [11]. Ten days post discharge; WBC had normalized. However, LFT' normalized only within 1 month of discharge. EBV IgG was positive at >750 and EBV early antigen at 52.1 U/mL, however EBV IgM was <10 U/ml. Parvovirus B19 IgG and CMV IgG were positive, however CMV and Parvovirus B19 IgM were negative. Patient continued to have spikes of fevers on the rst day despite the IVIG infusion. By the 5th day after IVIG, patients' conjunctival injection, myalgia and polymorphous rash had improved. Periungual desquamation had progressed to a severe desquamation of both hands and feet. A retrospective diagnosis of Kawasaki was then made, and the patient was discharged on Ke ex, Cetirizine and continued on low dose aspirin for 6 weeks.

Conclusion
This report of an adult case of Kawasaki disease may be bene cial to doctors of several medical specialties; like primary care physicians, Internists and intensivists as well as cardiologists, rheumatologists just to name a few. This case shows prolonged fever with thrombocytosis after day ve with thrombocytosis improving after aspirin administration on day ve. In the absence of other diagnoses, an incident of Kawasaki disease cannot be ruled out and it is worth noting that such a diagnosis should be highly suspected even as an adult patient without Asian descent. Figure 1 shows the liver function tests numbers for our 18-year-old KD patient. Figure 2 shows albumin levels increasing from the initial as KD progresses Figure 3 shows levels of granulocytes; neutrophils in our 18-year-old patient.

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