\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage{natbib}




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[ngerman,greek,english]{babel}



\usepackage{float}








\begin{document}

\title{BCG Induced Cold Abscess as a Complication of Inadvertent Vaccine
Injection, a Case Series}



\author[1]{Parinaz Sedighi}%
\author[2]{Taravat Sadrosadat}%
\author[1]{Mahsa Movahedi}%
\author[1]{Iraj Sedighi}%
\affil[1]{Hamadan University of Medical Sciences}%
\affil[2]{Tehran University of Medical Sciences}%


\vspace{-1em}



  
  \date{March 12, 2025}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup





\selectlanguage{english}
\begin{abstract}
We report a four-month-old girl with a right thigh swelling, an
eight-month-old girl with a left thigh swelling, and a five-month-old
boy with a left thigh swelling with the final diagnosis of BCG-induced
cold abscess as a result of erroneous injection of BCG vaccine into the
infants' thigh muscle.%
\end{abstract}%



\sloppy


\textbf{Title page}

\textbf{BCG Induced Cold Abscess as a Complication of Inadvertent
Vaccine Injection, a Case Series}

Parinaz Sedighi\textsuperscript{1, 2}, Taravat
Sadrosadat\textsuperscript{2, 3}, Mahsa Movahedi\textsuperscript{1},
Iraj Sedighi\textsuperscript{4*}

1.~ ~ ~ ~ ~ Student Research Committee, Hamadan University of Medical
Sciences, Hamadan, Iran.

2.~ ~ ~ ~ ~ Universal Scientific Education and Research Network (USERN),
Tehran, Iran.

3.~ ~ ~ ~ ~ Children's Medical Center, Pediatrics Center of Excellence,
Tehran University of Medical Sciences, Tehran, IR Iran.

4.~ ~ ~ ~ ~ Department of Pediatrics, Faculty of Medicine, Hamadan
University of Medical Sciences, Hamadan, Iran.

* Corresponding author: Iraj Sedighi, email address: sedighi@umsha.ac.ir

\textbf{Abstract}

We report a four-month-old girl with a right thigh swelling, an
eight-month-old girl with a left thigh swelling, and a five-month-old
boy with a left thigh swelling with the final diagnosis of BCG induced
cold abscess as a result of erroneous injection of BCG vaccine into the
infants' thigh muscle.

\textbf{Key words}

BCG Vaccine, Cold Abscess, Vaccines adverse effect

\textbf{Introduction}

The Bacille Calmette-Gu\selectlanguage{ngerman}érin (BCG) vaccine, as the only available vaccine
against Mycobacterium Tuberculosis, is recommended by the World Health
Organization (WHO) in numerous countries (1, 2). According to the
expanded program of immunization (EPI) in Iran, all children receive BCG
vaccination at birth. BCG is derived from live attenuated Mycobacterium
Bovis and there are possible local, regional or systemic complications
following the vaccine injection (2, 3). The strain of the BCG vaccine,
the child's immune response, and injection technique especially dosage
and administration route are considerable factors for the development of
the possible complications (4, 5). Mycobacterial infection is the most
common culprit for cold abscess, known as an abscess without severe
inflammation. The abscess also can be a result of incorrect
intramuscular BCG vaccine injection (6, 7). Here, we report three cases
of BCG-induced cold abscess as a result of erroneous injection of
vaccine into the infant's thigh muscle.

\textbf{Case presentation}

\textbf{Case 1:}

A four-month-old girl was presented to our hospital due to a right thigh
swelling since four days ago. The parents did not report any fever, poor
feeding, or irritability. On physical examination vital signs were
stable. There was a 5*7 cm fluctuating mass with sharp borders at the
anterior surface of her right thigh (Figure 1). No erythema, deformity,
discharge, or tenderness was detected. Both hips and knees had a normal
range of motion. The general physical examinations including lung and
heart auscultation, abdominal examination, and the examination of lymph
nodes were normal. There was no history of insect bite or trauma. The
patient had an appropriate growth and developmental history with no
prenatal or perinatal difficulties. She had received the routine
vaccination for Iranian children that included BCG, the first dose of
hepatitis B, the first dose of OPV (Oral Polio Vaccine), and the first
dose of DPT (Diphtheria, Pertussis, and Tetanus). The lab results were
as follows: White Blood Cell (WBC): 11500/\selectlanguage{greek}μ\selectlanguage{english}l (Polymorphonuclear
leukocyte (PMN): 29\% and Lymphocyte: 66\%), Hemoglobin: 9.6 gr/dl,
Platelet: 519000/\selectlanguage{greek}μ\selectlanguage{english}l, and Erythrocyte Sedimentation Rate (ESR): 50 mm/h.
Blood Urea Nitrogen (BUN), Creatinine (Cr), Blood Sugar (BS), and
electrolytes were normal. Ultrasound results demonstrated a large
collection of thick fluid (49*29*32 mm) with debris and septations in
the depth of the anterior thigh muscle. X-ray imaging was otherwise
normal.~ On the first day of admission needle aspiration of the lesion
was done and 5 milliliters of green purulent fluid was drained and sent
for gram staining, acid-fast staining, and culture. Gram staining and
routine culture were negative. The patient received intravenous
Cloxacillin without significant improvement and so open surgical
drainage was done and light yellow cheesy material was drained and sent
for acid-fast staining. Both samples sent for acid-fast staining showed
more than 10 acid-fast bacilli per field. On Loewenstein Jensen culture
media, light yellow slow-growing colonies were reported. The patient had
no abnormal findings on chest Computed Tomography (CT) scan and
immunological screening tests. The patient received Isoniazid, Rifampin,
and Ethambutol with diagnosis of mycobacterial cold abscess and there
was no improvement after three weeks. Clarithromycin was added and the
patient improved significantly after two weeks. These medications were
continued for four months and Isoniazid and Rifampin for further two
months. The patient had good growth and development with no further
re-accumulation of pus or any other remarkable health problem during the
one-year follow-up.

\textbf{Case 2:}

An eight-month-old girl was presented due to a left thigh swelling since
birth. There was erythema on the site for the first 40 days after birth
and then it was healed spontaneously but the swelling remained for eight
months and was exacerbated in the last three days before referral. The
patient's past medical history was unremarkable except for pneumonia
when she was one month old. At the time of admission, the patient had an
appropriate general condition; there was no fever, and other vital signs
were stable. On general physical examination, there was no abnormal
finding including no lymphadenopathy. There was a swelling mass sized
7*7 (cm) on the lateral side of the left thigh. There was no erythema or
inflammation on the site and it was not tender on palpation. Laboratory
findings showed WBC: 19900/\selectlanguage{greek}μ\selectlanguage{english}l (PMN: 20\% and Lymphocyte: 80\%),
Hemoglobin: 12.3 mg/dl, Platelet: 335000/\selectlanguage{greek}μ\selectlanguage{english}l, and ESR: 5 mm/h. BUN, Cr,
and liver function tests were within normal ranges. The ultrasound
examination of thigh soft tissue and X-ray of left femoral bone were
requested. Ultrasound results demonstrated an echo-free zone with a
thick wall (41*65*39 mm, approximately 57 ml, 6 mm under the skin)
containing faint debris in the depth of the left thigh muscle. The X-ray
was normal. The patient underwent surgical drainage and debridement of
the lesion. Before the surgery, needle aspiration of the lesion was done
and samples were sent for gram staining, acid-fast staining, culture,
and PCR examination of various mycobacterium types. Gram staining and
routine culture were negative. Acid-fast staining and culture on
Loewenstein Jensen culture media were both positive for Mycobacterium
Tuberculosis. The PCR test result was positive for Mycobacterium Bovis
(the subtype of Mycobacterium in the BCG vaccine). Also, Tuberculin Skin
Test (TST) was done and the result showed 0 mm induration. The patient
received Clindamycin after admission to cover possible causes of the
abscess. After a confirmed diagnosis of tubercular cold abscess,
clindamycin was discontinued and Isoniazid, Rifampin were started and
continued for the next six months. The patient had good growth and
development with no further re-accumulation of pus or any other
remarkable health problem during the follow-up.

\textbf{Case 3:}

A five-month-old boy was presented to the pediatric department as his
parents had noticed a progressive swelling and erythema on the left
thigh from one month ago. On physical examination vital signs were
stable. There was a swelling sized 4*4 cm on the left thigh and the site
was warm. No deformity, discharge, or tenderness was detected. The
general physical examinations including lung and heart auscultation,
abdominal examination, and the examination of lymph nodes were normal.
He had received oral Metronidazole and Amoxicillin-Clavulanic acid for
one week without any improvement. The patient had an appropriate growth
and developmental history with no prenatal or perinatal difficulties and
he had received the routine vaccination for Iranian children. The lab
results were as follows: WBC: 39000/\selectlanguage{greek}μ\selectlanguage{english}l, Hemoglobin: 9.8 gr/dl, Platelet:
510000, and ESR: 21 mm/h. BUN and Cr were normal. Ultrasound results
demonstrated a hypo-echoic lesion with internal septations (46*37*47 mm,
approximately 42 ml, 10 mm under the skin). X-ray imaging was otherwise
normal. Open surgical drainage was done and samples were sent for gram
staining, acid-fast staining, culture, and PCR examination of various
mycobacterium types. Clindamycin was administered after admission to
cover possible causes of abscess and due to inappropriate response, it
was changed to Vancomycin and Cefotaxime. Gram staining and routine
culture were negative. Acid-fast staining and culture on Loewenstein
Jensen culture media were both positive for mycobacterium. The PCR test
result was positive for Mycobacterium Bovis. TST was done and showed 0
mm induration. Isoniazid and Rifampin were administered after the
diagnosis of the mycobacterial cold abscess was confirmed. During the
next two weeks, regarding the thigh swelling and possible pus
re-accumulation, ultrasound examination of thigh soft tissue was
repeated and showed an abscess (approximately 9 ml, 19 mm under the
skin), so the patient underwent surgical drainage and debridement of the
lesion for the second time. Isoniazid and Rifampin were continued for
the next six months. The patient had good growth and development with no
further re-accumulation of pus or any other remarkable health problem
during the follow-up.

\textbf{Discussion and Conclusion}

Thigh swelling is a clinical sign of various infectious or noninfectious
underlying causes. Regarding the patients' physical examination cold
abscess was the most probable diagnosis since patients did not have
considerable warmness, erythema, and other signs of inflammation at
presentation. Mycobacterial infection is the most common cause of cold
abscess (6), so acid-fast staining was done along with routine culture
and was positive. Furthermore, a PCR test was done for confirmation of
diagnosis which was positive for Mycobacterium Bovis.

BCG is derived from live attenuated Mycobacterium Bovis and according to
the expanded program of immunization (EPI) in Iran, all children receive
BCG vaccination after birth (8). BCG is routinely injected intradermally
over the deltoid muscle. The abscess location in all patients was in the
anterior thigh muscle, the exact site of vitamin K and Hepatitis B
vaccine injection at birth. The positive PCR test for BCG Mycobacterium
Bovis and the abscess location raised the possibility of erroneous
injection of BCG vaccine into the infants' thigh muscle. We checked the
hospitals where case 2 and case 3 were born and found out that vitamin K
is injected by the midwife after that, BCG and hepatitis B vaccine is
injected by the vaccinator so the most probable situation is the
injection of 0.5 ml of BCG intramuscularly to the left thigh instead of
hepatitis B vaccine (Hepatitis B vaccine is routinely injected to the
left thigh). In case 1, regarding the presence of swelling in the right
thigh, probably 0.5 ml of BCG is injected intramuscularly instead of
vitamin K at birth (vitamin K is routinely injected to the right thigh).
The injection of a high dosage of BCG, 0.5 cc instead of 0.05 ml, and
intramuscular injection instead of intradermal are both factors for
BCG-related abscess which is observed in these cases. Similar cases of
BCG-induced cold abscesses are reported in Saudi Arabia and India. Verma
et al. reported a four-month-old girl from India. The patient presented
with a swelling on the anterolateral side of her left thigh since
receiving an intramuscular Diphtheria, whole-cell Pertussis, and Tetanus
(DwPT) vaccine injection at the age of six weeks. Fine needle aspiration
of the lesion showed caseating granuloma and staining for acid-fast
bacilli was positive. The most probable cause of the abscess, in this
case, is thought to be following erroneous BCG injection instead of DwPT
vaccine, and the diagnosis is not confirmed since the PCR test for BCG
Mycobacterium Bovis was not done. This type of error is not considered
for our cases because the BCG vaccine is not available in vaccination
centers in Iran and the error can only occur in hospital settings while
vaccine injection at birth. The article has mentioned that the swelling
was completely healed in six months without any anti-mycobacterial
therapy. But, we preferred to start treatment to speed up healing and to
prevent further complications (9). Also, Namshan et al. reported five
similar cases of BCG-induced cold abscess from Saudi Arabia. They did
not perform a PCR test for BCG Mycobacterium Bovis and the diagnosis was
based on culture results. Three cases received anti-mycobacterial drugs
and finally, all cases were healed without remarkable problems during a
two-year follow-up (6). The most extensive report is from Saudi Arabia
with 25 cases of BCG-induced abscess as a result of technical errors
during vaccine injection. The diagnosis was based on a positive smear
for acid-fast bacilli for all cases and a positive culture for 17 cases.
Nowadays, PCR test can detect the exact organism and help us for an
accurate diagnosis. In the later study the exact source and route of
infection was unknown but we tried to find where the error originates
from (10). Our recommendation to prevent this error is to assign
separated staff to inject each of the vaccines, injection of BCG and
hepatitis B vaccine in different rooms, and checking the vaccine
injection by a second observer. Also, WHO has warned that the correct
and precise BCG vaccine injection technique by trained staff is
important for optimal efficacy and safety of the vaccine (1).

\textbf{Key point}

Immunization errors while BCG injection like reconstitution error and
incorrect site are preventable so identification of these incorrect
practices is of great importance.

\textbf{Declarations}

Ethics approval: No identifiable information or picture has been mention
in the article. The Study has been approved by ethics committee at
Hamadan University of Medical Sciences. (Approval ID:
IR.UMSHA.REC.1400.532)

Conflicts of interest: Authors declare that there are no conflicts of
interest regarding the publication of this article)

Authors' contribution: Iraj Sedighi has been involved in the management
of patients. Parinaz Sedighi, Taravat Sadrosadat, Mahsa Movahedi, and
Iraj Sedighi contributed for data gathering and preparing the article.

Acknowledgement: The authors would like to thank staff of pediatrics
ward at Besat hospital for their great effort for patients' health.

\textbf{References:}

1. World Health Organization. BCG vaccine: WHO position paper, February
2018 - Recommendations. Vaccine. 2018;36(24):3408-10.

2. Erkens CG, de Vries G, Keizer ST, Slump E, van den Hof S. The
epidemiology of childhood tuberculosis in the Netherlands: still room
for prevention. BMC infectious diseases. 2014;14(1):295.

3. Venkataraman A, Yusuff M, Liebeschuetz S, Riddell A, Prendergast AJ.
Management and outcome of Bacille Calmette-Gu\selectlanguage{ngerman}érin vaccine adverse
reactions. Vaccine. 2015;33(41):5470-4.

4. Thamthitiwat S, Marin N, Baggett HC, Peruski LF, Kiatkulwiwat W,
Panumatrasmee V, et al. Mycobacterium bovis (Bacille Calmette-Guerin)
bacteremia in immunocompetent neonates following vaccination. Vaccine.
2011;29(9):1727-30.

5. Murphy D, Corner L, Gormley E. Adverse reactions to Mycobacterium
bovis bacille Calmette--Guérin (BCG) vaccination against tuberculosis in
humans, veterinary animals and wildlife species. Tuberculosis.
2008;88(4):344-57.

6. Al Namshan M, Oda O, Almaary J, Al Jadaan S, Crankson S, Al Banyan E,
et al. Bacillus Calmette-Guérin-related cold thigh abscess as an unusual
cause of thigh swelling in infants following BCG vaccine administration:
a case series. Journal of Medical Case Reports. 2011;5(1):472.

7. Millar TM, McGrath P, McConnachie CC. Tuberculosis of the spine
presenting with a cold abscess through the lumbar triangle of Petit.
Clinical Anatomy: The Official Journal of the American Association of
Clinical Anatomists and the British Association of Clinical Anatomists.
2007;20(3):329-31.

8. National Immunization Technical Advisory Group. Schedule and Guidance
of Immunization 8ed. Tehran2015.

9. Verma S, Didel S. Cold abscess of thigh following inadvertent
vaccination in an infant. The Indian journal of child health.
2016;3:76-8.

10. Kafeel G, Qadri SH, Pasha SAK, Sharif VA, Shakir SI. Development of
Subcutaneous Abscesses due to Mycobacterium Bovis Following Hepatitis
and Bacillus Calmette-Guerin Vaccination. Annals of Saudi Medicine.
1994;14(1):19-21.

\textbf{Figure 1:} Swelling with sharp borders at the anterior surface
of infant's right thigh (case 1)\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/figure-1/figure-1}

\end{center}
\end{figure}

\selectlanguage{english}
\FloatBarrier
\end{document}

