An unusual presentation of cysticercosis as a chest wall mass: A case report

Abstract

Cysticercosis is an infection caused by the tapeworm Taenia solium and most commonly affects the brain. Cysticercosis presenting as a chest wall mass is rare and can pose a diagnostic challenge. We report the case of a 4-year-old female child who presented with a 3-month history of a progressively increasing, painless swelling on the right lateral chest wall. Examination revealed a 2 × 3 cm, well-defined, cystic mass in the anterior axillary line. Ultrasound suggested a subcutaneous epidermoid cyst; however, histopathology showed the presence of scolices within the cyst, lined by giant cells, lymphocytes, and eosinophils, revealing the diagnosis of cysticercosis. The patient was treated with albendazole and is clinically stable. This case report highlights the importance of considering cysticercosis in the differential diagnosis of chest wall masses, particularly in endemic countries.

Introduction

Cysticercosis is a disease that is endemic in most developing countries and results from an infection with the tapeworm Taenia solium. It is acquired through direct contact with Taenia solium eggs from a patient with taeniasis, whereas taeniasis results from ingesting undercooked and infected pork.

Cysticercosis commonly presents as neurocysticercosis, but it can also affect other organs or tissues such as the eyes, muscle and subcutaneous tissue. Cysticercosis presenting as a chest wall mass is rare and can pose a diagnostic challenge due to the broad differential diagnosis. We report the case of a 4-year-old female child from southwestern Uganda diagnosed with cysticercosis presenting as a chest wall mass.

Case presentation

A 4-year-old female child presented with a 3-month history of a progressively increasing swelling on the right lateral chest wall. The swelling began as a small lump that gradually enlarged without associated pain, fever, or systemic symptoms. There was no history of trauma, insect bites, seizure, gait disorder or visual disturbance. She had no similar swellings elsewhere on the body. She had no personal or family history of pork consumption or known parasitic infections. Her past medical and family history was unremarkable.

Physical examination revealed a 2 × 3 cm well-defined mass in the anterior axillary line, cystic in consistency, non-tender, slightly mobile, with normal overlying skin (Fig. 1). There was no erythema, warmth, or discharge. There was no axillary, cervical, or supraclavicular lymphadenopathy. Examination of other systems was unremarkable, including a normal neurological exam.

Fig. 1.

Clinical photograph showing a well-defined mass (indicated by a white arrow) measuring 2 × 3 cm in the right chest wall along the anterior axillary line.

Investigations revealed a haemoglobin level of 12.8 g/dL, a white blood cell count of 9200/mm³ with mild eosinophilia (736/mm³), and a platelet count of 320,000/mm³. HIV test was negative. Stool examination did not show ova or parasites. Ultrasonography of the right chest wall showed a well-defined, thick-walled cystic lesion with intraluminal, non-shadowing echogenic solid nodules within the superficial muscles of the right lateral chest wall, measuring 2.73 × 0.92 cm. No enlarged axillary lymph nodes were noted, and the underlying and surrounding muscles were of normal caliber. The ultrasonography impression was a right lateral chest wall subcutaneous epidermoid cyst.

With a diagnosis of a subcutaneous epidermoid cyst, the cyst was surgically excised. Intraoperatively, a well-encapsulated cyst was found in the subcutaneous plane, adherent to the fascia but not infiltrating the underlying muscle. The cyst was completely excised intact and sent for histopathological examination. Histology confirmed cysticercosis, revealing scolices within the cyst, which was lined by giant cells, lymphocytes, and eosinophils. The patient was treated with albendazole at 15 mg/kg/day for 3 weeks and is clinically stable on subsequent follow-up visits. Neuroimaging could not be performed due to lack of parental cooperation.

Discussion

Cysticercosis, a disease caused by Taenia solium, is an endemic disease in most developing countries, including many African nations. A systematic review conducted across 16 countries in East and Southern Africa found that the seroprevalence of cysticercosis, measured using the antibody ELISA (Enzyme-Linked Immunosorbent Assay), could reach up to 45.3 % [1].

The life cycle of Taenia solium begins in humans, who are the definitive hosts, after ingestion of undercooked pork. After ingestion, the larvae mature in the small intestine into adult worms. The adult worms then produce eggs, which are excreted in the feces, resulting in a condition called taeniasis. The life cycle is completed in pigs following ingestion of the eggs, which subsequently develop into cysts within the pig's muscle tissue. When humans ingest Taenia solium eggs through contaminated food, water or hands, the eggs hatch into oncospheres, which penetrate the intestinal wall, enter the bloodstream, and can affect various organs, leading to cysticercosis [2]. Due to the fecal–oral transmission, individuals who do not consume pork, including vegetarians, can still develop cysticercosis [3], [4], [5].

Cysticercosis commonly affects the brain, with intraparenchymal neurocysticercosis being the commonest form. Extra-neural manifestations result from the involvement of organs and tissues like the eyes, muscle, and subcutaneous tissues. Disseminated cases of cysticercosis involving more than one organ can also occur [6], [7], [8].

Subcutaneous cysticercosis is less frequent than ocular or myocysticercosis. In one study of soft tissue cysticercosis biopsies, only 2 out of 21 cases were subcutaneous. In another study conducted on 55 patients with cysticercosis, 22 cases were extra-neural, and involvement of the skin and subcutaneous tissue was observed in only 3 patients [9], [10].

The most commonly involved sites in subcutaneous cysticercosis are the upper extremities, head and neck, and the anterior abdominal wall. Presentation as a chest wall mass is rare; hence, many cases are misdiagnosed as lipoma, osteochondroma, epidermoid cyst, abscess, or other soft tissue lesions [10], [11], [12]. In our literature review of reported cases, one case reported an 11-year-old male with a painless left anterior chest wall swelling; the diagnosis was made by ultrasonography and treated with surgical excision followed by antihelminthic therapy. Another report described a 34-year-old male with a painful right upper chest wall swelling diagnosed as myocysticercosis on ultrasonography and managed with non-steroidal anti-inflammatory drug (NSAID) and surgical referral. In both cases, the initial clinical impression included lipoma and abscess [13], [14].

The clinical manifestations of subcutaneous cysticercosis depend on the location, the number of cysts, and the patient’s immune response. The commonest symptom is a palpable swelling, which may be painless or painful. Some cases may even remain asymptomatic and are discovered incidentally. Painless swellings can become painful over time, usually following the death of the parasite, which causes inflammation within the surrounding tissue. The natural history of subcutaneous cysticercosis includes: a viable stage with a thin-walled cyst containing clear fluid and a scolex, a degenerating stage, a granular nodule stage, and a calcified, inactive stage [8], [15], [16].

The diagnosis of subcutaneous cysticercosis can be made using imaging or tissue sampling. In this regard, a high-resolution ultrasound is an important non-invasive diagnostic tool. Its classic feature is a well-defined cystic lesion containing a scolex and surrounded by peripheral edema [13]. However, depending on the stage of the disease, the classic findings may not always be present. Although magnetic resonance imaging (MRI) is the preferred modality for detecting and differentiating subcutaneous cysticercosis from other soft tissue masses, its utility is limited by cost and availability. Therefore, when ultrasound is inconclusive, the next step is usually fine-needle aspiration cytology (FNAC) or excisional biopsy [11]. Cysticercosis diagnosed in any organ warrants neurologic and ophthalmologic evaluation.

Treatment of isolated subcutaneous cysticercosis depends on the presence or absence of symptoms. Asymptomatic patients do not require any treatment. For symptomatic patients, management options include surgical excision, and/or antihelminthic therapy. Surgical excision is indicated when the diagnosis is uncertain, for a single swelling, in cases complicated by abscess, or for cosmetic reasons. Although surgical excision is considered curative, some authors from endemic areas recommend postoperative antihelminthic therapy. In patients with multiple swellings, antihelminthic medications such as albendazole or praziquantel can effectively eradicate the parasite and lead to resolution of the lesions [10], [13], [16], [17], [18], [19].

Conclusion

Cysticercosis presenting as a chest wall mass is rare and may pose a diagnostic challenge due to its unusual location and broad differential diagnosis. This case report underscores the importance of considering cysticercosis in the evaluation of chest wall swellings, particularly in endemic regions.

Author statement

All authors have read and approved the final manuscript.

The authors confirm that the work described has not been published previously, is not under consideration for publication elsewhere.

Author agreement

All authors have read and approved the final manuscript.

No specific funding was received for this work.

Written informed consent was obtained from the patient’s parents for publication of this case report and any accompanying images.

The authors confirm that the work described has not been published previously, is not under consideration for publication elsewhere.

CRediT authorship contribution statement

Abraham Sisay Abie: Writing – review & editing, Writing – original draft, Conceptualization. Eden Belay Tilahun: Writing – review & editing, Data curation, Conceptualization. Denis Oluka: Writing – review & editing, Data curation. Ayuel Isaac Abiel nyok: Writing – review & editing, Data curation. Lubega Ronald: Writing – review & editing. Felix Oyania: Writing – review & editing, Supervision.

Ethical approval

Not applicable. Written informed consent was obtained from the patient’s parents for publication of this case report and accompanying images.

Consent

Informed consent was obtained from the patient’s parents for publication of this case report and any accompanying images.

Funding

No funding was provided.

Declaration of Competing Interest

The authors declare that they have no competing interests in relation to this manuscript.