Clinical Rheumatology
https://doi.org/10.1007/s10067-022-06065-7
CASE BASED REVIEW
New‑onset Adult‑onset Still’s disease‑like syndrome after ChAdOx1
nCoV‑19 vaccination—a case series with review of literature
Shivraj Padiyar1 · Navaneeth Kamath2
T. Shashikala2 · Arvind Ganapati2
· John Mathew1 · A. S. Chandu1 · Divya Deodhar3 · B. A. Shastry2 ·
Received: 10 December 2021 / Revised: 11 January 2022 / Accepted: 12 January 2022
© International League of Associations for Rheumatology (ILAR) 2022
Abstract
We report a series of 3 Adult-onset Still’s disease (AOSD)-like presentations in previously healthy females following vaccination with the ChAdOx1 nCoV-19 vaccine, and also compare them with similar cases reported in literature
through a PubMed database search. Our first patient had a high spiking bi-quotidian type of fever with myalgia, sore
throat, and arthritis with onset 10-day post-vaccination, with laboratory features of hyper inflammation responding
to only naproxen. She was off treatment after 2 months. The second patient, with onset 3-week post-vaccination, had
a more severe illness, requiring high dose immunosuppression. In our third case, the onset of illness was slightly
delayed i.e., 3-month post-vaccination, but she had the most severe disease with macrophage activation syndrome at
presentation requiring immunosuppression and biologicals. The underlying mechanism may be linked to the activation
of Toll-like receptors (TLR)—TLR-7 and TLR-9—leading to a robust immune response. These 3 cases highlight the
immunogenicity of COVID-19 vaccines, with the possibility of occurrence of new-onset systemic hyper-inflammation
illness which can happen a few days following the vaccination, sometimes even delayed to months, and can range in
severity from mild to even life-threatening. More cases need to be studied to understand the profile and prognosis of
these syndromes in the long run.
Keywords Adult-onset Still’s disease · COVID-19 vaccine · Immunology
Introduction
The spread of COVID-19 infection has led to unprecedented rapid growth in vaccine development with a subsequent increase in the vaccination against COVID 19, with
many countries having vaccinated more than 50 percent of
* Arvind Ganapati
arvind_hegde1985@yahoo.com
Shivraj Padiyar
uspshiv@gmail.com
Navaneeth Kamath
navaneeth.kamath.12@gmail.com
1
Department of Clinical Immunology & Rheumatology,
Christian Medical College, Vellore, India
2
Department of Medicine, Rheumatology Division, Kasturba
Medical College, Manipal Academy of Higher Education,
Manipal, India
3
Department of Infectious Diseases, Christian Medical
College, Vellore, India
their population [1]. India also has completed 1000 million vaccinations since the inception of the vaccination
program in Feb 2021 [2]. Fever, chills, myalgia fatigue,
and arthralgia can occur following COVID-19 vaccination;
however, most of these symptoms are mild to moderate in
severity, occurring within the first 3 days of vaccination
and resolve within 1 or 2 days [3]. Although deemed safe
in the general population, systemic rheumatic diseases
have been shown to have flare-ups after vaccination [4].
In addition to this, there are reports of new-onset systemic
rheumatological diseases [5, 6]. The adjuvanticity of the
available SARS-CoV-2 vaccines is based on either TLR7/8 or TLR-9 agonism, which is a distinct mechanism from
previous vaccines [7]. ChAdOx1 nCoV-19 (Covishield)
vaccine, one of the many vaccines available in our country,
consists of simian adenovirus vector ChAdOx1, with fulllength spike protein of SARS-CoV-2 [8] Here we report
a series of 3 cases of new-onset Adult-onset Still’s disease (AOSD)-like syndrome following vaccination with
ChAdOx1 nCoV-19 vaccine.
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Clinical Rheumatology
Case 1
A 20-year-old previously healthy female, asymptomatic
4 weeks before admission, presented with high-grade
fever (102 degrees Fahrenheit), without chills. The fever
was bi-quotidian in nature, with asymptomatic phases in
between the fever spikes. This was also associated with
throat pain, generalized myalgia, and ankle arthralgia. In
a week, she also developed an evanescent maculopapular
rash over the neck, abdomen, and thigh during the height
of the fever. She had received her first dose of ChAdOx1
nCoV-19 vaccine 10 days before the onset of symptoms.
Her clinical examination at the time of admission was
unremarkable. On evaluation in an outside hospital, she
was found to have neutrophilic leukocytosis (Total WBC
count 15,600, N-72%) with elevated C-reactive peptides
(71 mg/L) and elevated ferritin levels (3500 ng/ml). The
investigations at presentation to us have been summarized in Table 1. Infectious disease (including polymerase
chain reaction for SARS-CoV2 and blood culture) and
malignancy workup with Positron Emission Tomography–Computerized Tomography (PET-CT)/bone marrow
examination were normal. Serological workup for other
autoimmune diseases was negative. She was diagnosed
with AOSD based on the Fautrel’s criteria [9]. She was
initiated on Tab. Naproxen 250 mg twice daily which she
had immediate resolution of symptoms of fever and myalgia. She remained afebrile during the remaining stay in
Table 1 Baseline investigational
parameters of the 3 cases
the hospital. She had improvement in her inflammatory
parameters at discharge (Table 1). She was continued on
anti-inflammatory agents for 4 weeks. She was reviewed
telephonically 2 months later and reported to be asymptomatic and has remained off medications since. The course
of the patient’s clinical presentation and management has
been summarized in Fig. 1.
Case 2
A 47-year-old, previously healthy woman presented with
high-grade fever (101 degrees F), quotidian in nature for
the last 2 months. This was associated with small and large
joint inflammatory arthritis, without any rash. She also had
a history of associated significant weight loss and loss of
appetite of the same duration. She had a history of ChAdOx1
nCoV-19 vaccine 3 weeks before the onset of symptoms. She
had a partial response to oral methylprednisolone therapy
16 mg/day prescribed by a general practitioner. She also
gives a positive history of rheumatoid arthritis (RA) in her
elder sister. Clinical examination revealed pyrexia with tachycardia (Pulse rate -104 beats per minute) and swollen and
painful knee and wrist joints. On evaluation, she was found
to have a hemoglobin of 8.1 g/dL, platelet count of 5.54
lakh/mm3, and a white blood cell count of 12,100 cells/mm3
with a neutrophil predominance. She was also found to have
elevated liver enzymes and elevated inflammatory markers
Parameters
Case 1
Case 2
Case 3
Normal range
Hemoglobin (g/dl)
Total leukocyte count (cells/cumm)
8.1
12,100
(N-82%)
5.54
169
86
29
60
0.53
404
< 10.1
1
Negative
Negative
Normal
Echocardiography
Normal
Bone marrow
Normal
Mild
pericardial
effusion
Normal
10.6
11,700
(N-75%)
2.24
227
48
478
239
0.8
> 100,000
Negative
Negative
Negative
Negative
Cervical and Inguinal
lymphadenopathy
Normal
13.5–17.5
4000–12,000
Platelets (lakh cells/cumm)
CRP (mg/l)
ESR (mm/hr)
SGOT (U/L)
SGPT (U/L)
Creatinine (mg/dl)
Serum ferritin (ng/mL)
RF (IU/ml)
Anti-CCP (RU/ml)
ANA (done by IF)
Blood cultures
Imaging—CT scan/PET-CT
9.7
10,400
(N-73%)
2.54
38
51
176
262
0.59
11,491
< 10.1
Negative
Negative
Normal
150,000–450,000
<6
< 15
8–40
5–35
0.5–1.4
20–300
< 20
< 10
Negative
Negative
Consistent with HLH
RF rheumatoid factor, ANA antinuclear antibody, IIF indirect immunofluorescence, Anti-CCP anti-cyclic
citrullinated peptide
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Clinical Rheumatology
Fig. 1 Clinical course and laboratory values of patient 1 over time
(Table 1). Her nasopharyngeal swab for SARS COV 2 by
RT-PCR was negative. Cross-sectional imaging of the thorax
and abdomen did not show hepatosplenomegaly and bone
marrow examination ruled out the possibility of infection or
malignancy. An echocardiogram showed mild pericardial
effusion. Serology for autoimmune diseases was negative.
After excluding infectious, malignant, and autoimmune
etiologies, a possibility of AOSD was considered based on
Fautrel’s criteria [9]. Her fever resolved following 20 mg/kg
naproxen; however, arthritis needed 0.5 mg/kg oral prednisolone. Since the patient refused consent for higher doses of
steroids, she was started on Inj Tocilizumab 162 mg subcutaneously every 2 weeks with low dose methotrexate. She
was reviewed after 1 month telephonically at which point,
she had remarkable improvement in her symptoms. A decision regarding further tocilizumab will be done at 3 months
review. The course of the patient’s clinical presentation and
management has been summarized in Fig. 2.
Case 3
A 35-year-old lady with no previous co-morbidities presented to us with high-grade fever, sore throat, evanescent skin rash on the trunk/extremities, and arthralgias
for 2 weeks. There was a history of associated weight loss
Fig. 2 Clinical course and laboratory values of patient 2 over time
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Clinical Rheumatology
during her morbid period before the presentation. She
received her first dose of the ChAdOx1 nCoV-19 vaccine
3 months before the onset of illness. On examination, she
was febrile with tachycardia (110/minute). Cutaneous
examination showed pink maculopapular rash over the
trunk and extremities. Generalized lymphadenopathy was
noted. Other systemic examination was unremarkable. Her
laboratory tests revealed hemoglobin (Hb) of 10.6 g/dl,
white cell counts of 11,700 cells/mm3 with 75% neutrophils, and a platelet count of 2.24 lakhs/mm3. Her C-reactive peptide (CRP) was 227 mg/L. She had elevated liver
enzymes (aspartate transaminase of 478 IU/L and alanine
transaminase of 239 IU/L) with normal bilirubin levels,
elevated lactate dehydrogenase (LDH) (> 1000 U/L), and
hyperferritinemia (> 1,00,000 ng/ml). The same has been
summarized in Table 1. Fasting serum triglycerides was
336 mg/dL. Her procalcitonin levels were not elevated.
Infectious disease workup comprising of 2 sets of blood
cultures, nasopharyngeal swab for COVID-19 PCR,
echocardiogram, serological tests for Hepatitis A/E/B/C,
multiplex polymerase chain reactions (PCR) for Rubella/
Epstein Barr virus/Parvovirus B19/Measles/Cytomegalovirus and tropical fever screening were all negative. PETCT of the whole body showed mild FDG avid bilateral
cervical lymphadenopathy in Level I, II, III, and Level
V nodes. A cervical node biopsy showed only a reactive
lymphadenitis picture with no evidence of granulomas or
Fig. 3 Clinical course and laboratory values of patient 3 over time
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lymphoma. Autoimmune disease serologies were negative. During the hospital stay, the fever which was double quotidian in pattern became remittent and she had a
drop in blood counts. Bone marrow studies showed no
malignancy or infection and confirmed the presence of
macrophage activation. A possibility of Adult-onset Still’s
disease with macrophage activation syndrome was considered. She fulfilled both Fautrel’s [9] and Yamaguchi’s
criteria [10]. She had multi-organ dysfunction in the form
of acute respiratory distress syndrome (ARDS) due to
diffuse alveolar hemorrhage (DAH) requiring non-invasive ventilation and hepatic failure (AST 515 IU/L, ALT
1294 IU/L, ALP 308 IU/L). She was immediately started
on intravenous (IV) pulse methylprednisolone (MP) of 1 g
for 3 days with intravenous immunoglobulin (IVIg) 2 g/
kg over the next 5 days. We followed up this therapy with
oral dexamethasone of 10 mg/m 2 as per the HLH-2004
protocol [11]. She improved 5 days following this management with rapid clearance of her DAH accompanied
by a rise in hemoglobin and blood counts; however, there
was no improvement in liver function tests. She further
received 480 mg (8 mg/kg) of IV tocilizumab, following which there was a significant improvement in liver
function tests. She was discharged on oral prednisolone
1 mg/kg and planned for tocilizumab therapy for the next
3 months. The course of patient management has been
summarized in Fig. 3.
Clinical Rheumatology
Discussion
AOSD is a multisystem inflammatory disorder of unknown
etiology commonly affecting young adults. This is mainly
a diagnosis of exclusion, done by a constellation of clinical
and laboratory criteria. The cardinal symptoms consist of
fever, arthritis, evanescent rash, sore throat, hepatosplenomegaly, and even life-threatening complications, including
fulminant hepatitis and macrophage activation syndrome
(MAS) [12]. The predominant laboratory abnormalities
include anemia, thrombocytosis, neutrophilic leukocytosis, transaminitis, and hyperferritinemia. Abnormal activation of the innate and adaptive immune system leading
to uncontrolled production of cytokines, including IL-1β,
IL-6, IL-18, and TNF-α, has been recognized as a cornerstone in AOSD pathogenesis [13]. SARS-CoV-2 infection
similarly provokes a hyperinflammatory state driven by
IL-6, IL-1α, IL-1β, and TNF-α [14]. There have been studies comparing the similarity and differences among AOSD
and cytokine storm of COVID-19 [15]. Severe COVID19 associated cytokine storm is also a hyperferritinemia
state which further enhances pro-inflammatory cytokine
release [16, 17]. Various autoimmune and rheumatological disorders have been reported among the COVID-19
affected patients and also flare-up of certain underlying
rheumatological conditions [6]. Conversely, AOSD is a
multisystem auto-inflammatory disorder that can be triggered by viral infections, bacterial infections, or rarely
even vaccines in a genetically susceptible individual.
Wan-Hee-Yo in his cover letter to the editor also reports
a case of AOSD following influenza vaccination [18]. A
few differences however do exist between the two disease
states. AOSD has a higher female preponderance which is
consistent in our case series. All the 3 cases reported by
the authors are female patients [19, 20]. One of the oddities was normal platelet counts in cases 1 and 3. Although
thrombocytosis is common in AOSD, it is not a must for
diagnosis. There have been many cases reported in the
literature where platelet counts are normal [29]. The proportion of elevated liver enzymes and elevated C-reactive peptides was higher in AOSD patients compared to
COVID-19 cytokine storm patients. AOSD is characterized by much more elevated ferritin levels compared to the
COVID-19 cytokine storm [15]. The cytokines like IL-1,
IL-6, and IL-10 were higher in severe COVID-19 compared to AOSD. The common role of IL-1 and IL-6 in the
pathogenesis of AOSD and COVID-19 could explain the
close similarities between both diseases. cases reported in
the literature on the development of AOSD after COVID19 infection [21, 22]. Apart from the COVID infection,
vaccination per se can also cause a new onset AOSD-like
syndrome. A PubMed database search done on 2/1/2022
using key words “Still’s disease and COVID vaccination” yielded 3 case reports that have been published in
literature [23–25] (Table 2). Two main mechanisms have
been postulated in the development of autoimmunity to
vaccines: one is molecular mimicry and the other is nonspecifically known as “bystander activation” [26]. Studies
have shown that the SARS-CoV-2 spike protein can act as
a pathogen-associate molecular pattern (PAMP), thereby
causing an overproduction of cytokines via the TLR-mediated pathways and also the inflammasome pathway [27,
28]. Activation of TLR-7 and 9 can lead to upregulation
of Interferon stimulated Genes (ISG) leading to robust
Table 2 Comparison between various post-COVID vaccine AOSD syndromes reported in the literature
Case 1
Case 2
The onset of
symptoms after
vaccination
Duration of symptoms
Criteria met
Treatment
20/F
ChAdOx1 nCoV19
10 days of the first
dose
47/F
35/F
ChAdOx1 nCoV- ChAdOx1 nCoV19
19
3 weeks of the first 3 months of the
dose
first dose
3 weeks
2 months
1 month
Fautrel’s
Naproxen
Fautrel’s
Methotrexate,
Tocilizumab
Follow up
Response
2 months
Improved
1 month
Improved
Yamaguchi
MP Pulse
IVIG—2 g/kg
Tocilizumab
(8 mg/kg)
15 days
Improved
Age
Type of Vaccine
Case 3
Magliulo et al.
(2021)
Leone et al.
(2021)
45/F
mRNA-1273
36/F
ChAdOx1 nCoV19
5 days of 2nd dose, 4 days of 1st dose
30 days of 1st
dose
2.5 weeks
3 weeks
Baicus et al. (2021)
22/M
BNT162b2
13 days of the first
dose
1 month
Yamaguchi
Yamaguchi
Steroids (1 mg/kg) MP pulse, anakinra
Fautrel’s
Mp pulse, IVIG,
anakinra
3 weeks
Improved
1 month
Improved
1 month
Improved
MP methylprednisolone, IVIG intravenous immunoglobulin
13
Clinical Rheumatology
innate immune responses. The symptom onset in all 3 of
our cases being later than 1 week following vaccination
and symptom constellation lasting > 3 weeks emphasizes
the point of these presentations being likely due to a distinct immunological hyperactivation entity, unlike the
immediate post-vaccination immunological phenomena.
Our first patient had a less severe disease that responded
to only naproxen; however, the second patient had a more
severe disease. The third patient had a life-threatening
presentation requiring intravenous immunoglobulin, pulse
steroids, and anti-cytokine therapy to control the disease
activity. The time difference between the COVID vaccination and AOSD-like presentation was relatively short (days
to weeks) in the first two cases; however, it was slightly
delayed (3 months) in Case 3. The delayed onset as in
Case 3 is also in contrast to the recently reported cases of
AOSD-like state following COVID vaccination, which had
onset ranging from 5- to 13-day post-vaccination [22–24].
Such observations highlight the point that hyperinflammatory state following COVID19 vaccination can be variable
in severity from mild to life-threatening disease and can
present early (in days/few weeks) or occur as a delayed
presentation (up to 3 months).
At this point, the nomenclature of the abovementioned
presentations seems difficult and could be debatable. Such
presentations could turn out to be a monophasic illness in
contrast to the variable course of AOSD. However, similar
cases from across the globe need to be reported and longterm follow-up of our patients is imperative to conclude on
this aspect. With this case series, we can only postulate the
COVID vaccination to be the most probable inciting trigger
for an AOSD like presentation; however, a definite causal
relationship can only be established with the help of epidemiological studies from countries with good data-keeping
and surveillance for vaccine-induced immunological adverse
events and population data of annual incidence of AOSD.
Conclusion
Clinicians must be alert to the possible occurrence of
new-onset early or delayed presentation of an AOSD-like
syndrome following ChAdOx1 nCoV-19 vaccination. The
presentation can range from being mild to extremely lifethreatening. Timely identification and institution of appropriate anti-inflammatory therapy based on the severity of
presentation would be imperative.
Acknowledgements We would like to thank Dr. Prabhu Vasanth for
his contributions to the manuscript.
Author contribution SP: original hypothesis, conceptualisation,
literature review, writing–original draft, review, and editing; NK:
13
conceptualisation, literature review, writing–original draft, review,
and editing; JM: writing–original draft, review, and editing; CAS:
conceptualisation, writing original draft–review and editing; DD: conceptualisation, review, and editing; BAS: conceptualisation, review,
and editing; ST: conceptualisation, review, and editing; AG: original
hypothesis, data review, data interpretation, manuscript preparation;
writing–review and editing.
Data availability Data would be made available on request.
Declarations
Informed consent Written informed consent has been obtained from
all the patients before preparing this manuscript.
Conflict of interest AG reports receiving an honorarium for an invited
guest lecture from Chugai Pharmaceuticals, Japan, outside the scope
of this study. SP, NK, JM CAS, DD, BAS, and ST have no conflict of
interest to declare.
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