The Journal of the Arkansas Medical Society Med Journal May 2019 Final 2 | Page 20

CASE STUDY
Good’s Syndrome: It’s Good to Have a Diagnosis
Naga Saranya Addepally, MD
ABSTRACT
ood’s syndrome is a rare condi-
tion with combined immunodefi-
ciency and thymoma. We present a
G
patient with severe, chronic diarrhea and history of
thymoma. Workup showed markedly reduced lev-
els of immunoglobulins. Treatment with intravenous
immunoglobulins resulted in significant improve-
ment in diarrhea and weight gain.
Keywords: Good’s syndrome; Thymoma; Hy-
pogammaglobulinemia
INTRODUCTION
Good’s syndrome (GS) is a rare disorder char-
acterized by combined humoral and cellular im-
munodeficiency associated with thymoma. It mani-
fests a variety of recurrent infections. We present a
case of chronic diarrhea in a patient with a history
of resected thymoma many years prior to presenta-
tion. We briefly discuss the pathogenesis, presenta-
tion, and treatment of GS.
CASE PRESENTATION
A 50-year-old gentleman was evaluated for
chronic diarrhea with duration of eight years. He
reported having 8-15 loose stools every day along
with unintentional weight loss of 100 pounds in
the last year. He reported that stools were loose in
consistency accompanied by abdominal cramps.
There was no history of blood in stools. Diarrhea
would wake him up from sleep, and he experienced
diarrhea despite fasting. His past medical history
was significant for incidental thymoma (status post
thymectomy about 10 years ago). Extensive labo-
ratory workup to rule out infectious etiology, fat
malabsorption, celiac disease, and inflammatory
bowel disease was negative. Colonoscopic exam
was normal with random right- and left-sided bi-
opsies showing mild focal active colitis; terminal
ileum was normal. Trial of steroids and oral mesala-
mine failed to improve symptoms. After multidisci-
plinary evaluation considering history of thymoma
and chronic diarrhea, we suspected GS. Serum
quantitative immunoglobulins were found to be
extremely low: IgG 55 mg/dL, IgA <25 mg/dL, IgM
<17 (references values: 700-1600 mg/dL, 70-400
mg/dL, and 40-230 mg/dL respectively). Upon flow
cytometry, B-cells were undetectable (<1% of total
lymphocytes). These findings confirmed the diag-
nosis of GS. Patient was initiated on treatment with
monthly Intravenous Immunoglobulin (IVIG). He ex-
perienced significant improvement of diarrhea over
the following few weeks (1-2 formed stools/day)
and had a 24-pound weight gain in two months.
DISCUSSION
Good’s syndrome is a rare cause of combined
immunodeficiency seen in adults and is character-
ized by a triad of thymoma, immunodeficiency, and
hypogammaglobulinemia. This acquired immuno-
deficiency usually manifests in late adulthood and
affects both cell-mediated and humoral immune
system. Immunodeficiency in these patients puts
them at risk of recurrent sino-pulmonary infections
and many opportunistic viral, bacterial, and fungal
infections. The first case was reported by Rob-
ert Good in 1954. 1 Around 3-6% of patients with
thymoma have concomitant hypogammaglobu-
linemia. 2,3 GS usually manifests in the 40- to 50-
year age group, with equal predominance in males
and females. Although GS can present in children,
it is very rare. According to the systematic review
of more than 150 patients on Good syndrome, the
incidence of GS in highest in the Europe. 4
The pathogenesis of GS is heterogeneous. The
primary immunologic abnormalities in this disease
are hypogammaglobulinemia, reduced number of
B cells, and CD4+ T lymphocytes. 4 Hypogamma-
globulinemia was found in 100% of patients with
GS across two reviews. A hypothesis suggests that
certain cytokines arrest or impair B-cell matura-
tion, leading to the above defects. 5 Abnormalities
in CD4+:CD8+ T cell ratio are also commonly
seen, and many of these patients have cutaneous
anergy to two or more test antigens. Good’s syn-
260 • THE JOURNAL OF THE ARKANSAS MEDICAL SOCIETY
drome is also commonly associated with anemia,
leukopenia, and thrombocytopenia. Some mani-
festations, like pure red-cell aplasia (PRCA) seen
in GS suggest an autoimmune component in either
etiology or pathogenesis of the disease. 6
The initial presentation of GS can be varied. In
many patients, the diagnosis of thymoma is usu-
ally preceded by recurrent infections with intervals
of months to years. Thymoma is a slow-growing
neoplasm presenting as a mediastinal mass.
It can be a benign tumor or a malignant tumor
that is capable of distant metastasis. Due to the
location of tumor, it can present with respiratory
symptoms including cough, dyspnea, hoarseness,
chest pain, dysphagia, or compression symptoms
including superior vena cava syndrome or Horner’s
syndrome. In some patients, it can be totally as-
ymptomatic and found only incidentally. As these
patients have defects in both cellular and humoral
immunity, they are susceptible to a variety of re-
current infections. The most common bacterial
infections reported in these patients is recurrent
sino-pulmonary infections, especially with encap-
sulated organisms. 7 Hemophilus influenza (24%),
pseudomonas (22%) and Klebsiella (13.2%) are
the three most common organisms isolated. 4
Bacteremia, urinary tract infections, and bacterial
diarrhea are the other common bacterial infec-
tions. Other infections reported include mycobac-
terial infections; viral infections with CMV, VZV, HSV,
JC, HHV-8 and HPV; and fungal infections with
Candida, Aspergillus, and Pneumocystis jiroveci. 4
Though uncommon, parasitic infections were also
reported in these patients. It is important to note
that chronic diarrhea is the presenting symptom
in 50% of patients, as was the case in the patient
we are reporting. While infectious etiology is the
most common cause of diarrhea, malabsorption
secondary to villous atrophy or immune-mediated
colitis has also been reported. Salmonella, clos-
tridium, Giardia, and CMV are a few organisms as-
sociated with diarrhea in these patients. However,
in many patients, a definitive organism was not
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