1 Background
1.1 Chemotherapy-Induced Bone Marrow Suppression
In 2020, among new cancer cases worldwide, breast cancer officially
overtook lung cancer as the most prevalent form of cancer, accounting
for 11.7% of all new cancer patients [1]. With continuous
improvements in tumour treatments, there are now numerous therapeutic
options for breast cancer. However, regardless of the chosen approach,
chemotherapy still holds a prominent position [2]. Over several
decades of development, chemotherapy drugs and regimens have continually
advanced. Now, they play a crucial role in prolonging patient survival
and enhancing their quality of life. However, various side effects from
chemotherapy should not be underestimated, with bone marrow suppression
being the most severe [3]. It mainly manifests as a reduction in red
blood cells, white blood cells, and platelets. Consequently, conditions
such as anaemia, infections, and bleeding may occur, resulting in
adjustments, interruptions, or delays in chemotherapy. In severe cases,
the patient’s life may even be endangered. Studies have suggested that
the occurrence of bone marrow suppression is closely related to clinical
factors such as the chemotherapy drug type, combined or sequential
regimens, chemotherapy cycles, chemotherapy drug dosage and density
[4], and even patient ethnicity [5].
1.2 Bacterial Pyogenic Liver Abscess
Pyogenic liver abscess is the
most common infectious disease that affects the liver. The most
prevalent form is bacterial pyogenic liver abscess, which is caused by
invasive bacterial infections and accounts for approximately 80% of all
pyogenic liver abscesses. In recent years in China and the Asia-Pacific
region, there has been a gradual increase in pyogenic liver abscess
cases caused by Klebsiella pneumoniae, which has replaced Escherichia
coli as the primary pathogenic bacterium that causes bacterial pyogenic
liver abscess [6,7]. Clinical manifestations of bacterial pyogenic
liver abscess primarily include fever, chills, and, in some cases, right
upper abdominal pain, nausea, vomiting, fatigue, weight loss, and
jaundice. Clinical diagnosis relies on a combination of the patient’s
symptoms, physical signs, inflammatory indicators such as blood routine,
C-reactive protein, or procalcitonin, imaging examinations like
abdominal ultrasound, CT, or MRI, as well as results from blood and
puncture fluid bacterial cultures. Treatment options generally involve
systemic anti-inflammatory therapy, ultrasound or CT-guided percutaneous
drainage of the pyogenic liver abscess, and surgical intervention. Due
to the potential for haematogenous dissemination in the early stages,
Klebsiella pneumoniae pyogenic liver abscess (KPPLA) can easily lead to
Klebsiella pneumoniae invasive syndrome, which often involves the lungs,
central nervous system, and eyes [8,9].
1.3 Endogenous Endophthalmitis
Endogenous endophthalmitis (EE), also known as metastatic
endophthalmitis, is a severe, vision-threatening intraocular infection
caused by pathogenic bacteria in the bloodstream that penetrate the
blood-ocular barrier and enter the intraocular environment. As the most
serious complication of KPPLA, EE has an incidence rate of approximately
4.5% [10,11]. In its early stages, EE lacks distinct characteristic
features, making initial diagnosis challenging and often leading to
misdiagnosis. The progression of EE is rapid and the prognosis remains
poor, even in cases that receive timely treatment [12]. Severe cases
often lead to blindness and sometimes require enucleation of the eye. In
this article, we review the clinical data of a patient who was admitted
to our hospital with chemotherapy-induced bone marrow suppression
combined with pyogenic liver abscess resulting in EE. A comprehensive
analysis is provided based on the patient’s case and the relevant
literature.